How do I handle myself in this?
My boyfriend and I have lived together for about 4 months now and that's how I finally realized what I am getting myself into. We are not engaged yet but he is constantly talking about marriage and how we are going to grow old together so I know he's serious about having a life together with me and I am him. However I have this struggling thoughts about his two kids. The "thinking" part of me tells me that I should be ok with them, at least like them if not able to love them. However the "feeling" part of me constantly hoping they would be out of the picture. I don't know how not to feel the way I feel. The worst part is they are normally quiet, almost withdrawn when people they don't know are around, but when they are with each other or with their dad, they are loud and won't shut up and the "happy times" they spend with the BM keep coming up in their conversation. My boyfriend said they were just being kids and he couldn't stop them from talking about the fun time they had with their mother in front of me. This is very difficult to tolerate, it made me feel like an intruder in "their" family. My real big dilema is once a year my boyfriend will take them on a 2-week trip, it takes about 6 to 7 hours in the car to get to the destination. Of course my boyfriend expects me to go with them and that's what troubles me. How am I to sit in a car with them for 6, 7 hours putting up with them talking and screaming non-stop and listening to my boyfriend and them chatting about the "good old days" with the BM? If I don't go with them, first, my boyfriend might have a problem with it even though he knew I am not a kid person, and second, 2/3 of our vacation time will pretty much go down the drain since he only has 3 weeks vacation each year. I keep daydreaming that he never had kids with his ex. I hate the thoughts of hoping for the kids to disappear. I feel like a wicked person. I thought about leaving him but we are both committed to each other, it's hard to just throw it all out the window. I know talking about it probably won't solve anything, but it's still good to talk about it, maybe someone out there can understand and sympathize without judging. Plus I really need to have someone outside of his family to talk to. How on earth can I talk about my true feelings about his kids to his family without being executed on the spot? 
I had some of these feelings
I had some of these feelings when I first met my boyfriend. I think a lot of us have had those daydreams. Of course your lives would be simpler if there weren't any children but the fact of the matter is the children (and the ex in most cases) are never going to go away. So if you are going to stay with this man, that is something you need to come to terms with. Also, they are never going to stop loving their mother and if they have a good time with her that's better than her abusing them in some way. Just because your boyfriend doesn't love his ex anymore doesn't mean the children can't either. She will always be their mom. As for the vacation with the children, if the children don't act out and treat you poorly then why does it bother you? Just enjoy the time with your boyfriend and be happy that he's not trying to take his ex along too. I've read lots of stories on this site where that happens. Remember, he is their father and this two week trip is obviously something that they all enjoy. Your boyfriend wants YOU to be part of that, I think that's a lot better than him wanting you to stay home. In a relationship like this I think it's important for potential step parents to keep in mind how they want their lives to be. Being a step parent is about constant compromising personal feelings and personal sacrifice. Just think about what you want and if what you want is your boyfriend but only without his children then that's not going to happen. You'll need to end your relationship and find a person who doesn't have children. I know it's hard to have "break up or deal with it" be your only options but in a lot of aspects of step parenting, those are what your options are going to be. Some things are worth fighting over and discussing but in this case, this is a battle you won't win.
I too have to deal with these
I too have to deal with these feelings, SD11 is the princess of the house and has no responsibilities in "our family" She is here every week from Thur to Sat on 1 week,then Thur to Sunday pm on the other, half the time to me, but not enough time for DH, she should not have chores because "he doesn't see her often and her time should be with daddy". So they have their time together, excluding me much of the time, although according to DH I exclude myself. At this point I can no longer ask her to do anything, no discipline on my part and I am getting more miserable as time goes on. On the days she is not here, DH gives me the silent treatment. It is very stressful. I mentioned to DH I had reservations about being in the truck with them 2 full days of driving for vacation in July. And well you could feel that proverbial bomb drop, now he won't talk to me. But today, {I took the day off to babysit as originally planned) he took her with him to work and back to BM. so I missed out on working and have the day to my self. After being mad, I got glad and am doing what I want to do today without the princess lounging about, and that is how I deal with it. It remains to be seen if I will vaca with them or stay home in a peaceful house.
What you are feeling is
What you are feeling is normal. You are not wicked. No one knows they are going to feel this way until after they are in this situation. Had I known I would feel this way I would have avoided men with children still living at home. Chances are you will always feel this way. Ask yourself is he worth it? Does he treat you like a queen with the utmost respect? If not I'd ditch him and find a guy without kids. How often does he have his kids? Those people who only see their stepkids every other weekend I don't know what they are so upset about. It is much harder when the custody arrangement is 50/50.
It's 50/50 arrangement so
It's 50/50 arrangement so they are here some time during the week as well. When they are here, they will have some neighbor kids come over running around the house too. I basically lose my privacy and personal space so when I can I will go out for a walk or to the stores just to have some peace and quiet. And usually when I come back the sink will be full of dirty dishes (BF cooks for them and makes a mess), I just pretend I don't see anything. My BF treats me nice and tries to make me happy when they are not around, I constantly tell myself he's worth it, worth the wait. He said when they are 18, things could be different, they are 11 and 12 now. But the fact is I still have to live through these 7 years, I can't take a sleeping pill and wake up 7 years later. I am constantly struggling. The BM hates me from day one since my BF divorced her against her will for her infidelity. She suggested an open marriage before the divorce and that was a joke to my BF. I have never met the BM while she kept demanding to meet me. My BF said she will never get a chance to meet me because she's a piece of dirt (he actually used a much worst word to describe her). I really wish he never had kids with her but what is done is done. I still have no idea what is going to happen on the trip thing. Flower Girl, hope you find a way to cope with the July trip.
I was in a similar situation
I was in a similar situation before DH and I got married. The disgruntled feelings with sd have steadily grown, but my dh normally supports me. His family is just like that-the sd is "SO good" and she hung the moon. Its disgusting really how mil acts like she should get her allotted time with sd just like my dh does. And they love bringing up bm. Whatever- I didn't marry him for his family
Have you talked to your SO about your feelings much? Maybe you should do that and see how he feels/reacts. If this upsets him because he is siding with his children and not listening to you and your feelings (if he DOES intend to marry you, he needs to attend to you and make you happy...) then maybe its time to walk away. Walking away is always the hardest part, but don't spend your life unhappy. Good luck:)
Maybe you could try
Maybe you could try explaining to him that because you're not very maternal you're going to find it difficult to spend that amount of time stuck in a car with kids, any kids, its not personal to his kids. He should be open to you taking an iPod or something so that you can plug in the headphones for an hour or so. Also, try to negotiate that a percentage of the trip is spent reading, after all, it is your trip too and it shouldn't be a completely stressful time.
Its not fair of him to expect you to make all of the compromise. I also had this problem as my guy's response was, well this is what we've always done. We discussed (argued like crazy)until I finaly realised why I was feeling so resentful and was able to explain that I am always the one bending and this is my life too. So if we are going to be able to spend our lives together the compromise must come in all directions. Just because they have always gone away for 2 weeks doesn't mean its the law! Maybe this could change to 1 week away and 2 weekends away with the kids per year to break it up a little for you. If you're not so stressed, hew's not so stressed making it a nicer time all round and more exciting for the kids if they get to go away with their dad and you more than once a year !
Yes you got together with a man with kids but he also got together with a woman without kids. It works both ways.
The kids will always bring their mother up and they probably don't even realise that this could hurt your feelings or p*ss you off. I'm afraid that one is a case of biting your tongue and smiling politely! The mother of my step kids sounds similar to the mother of yours and she tries to make life hell for us but you have to do what is right for the kids because at the end of the day, its not their fault that we don't want/don't have kids of our own. I regularly help the step kids bake mother's day cakes, easter cakes and all the rest of it whilst quietly developing a stress ulcer and smiling sweetly becasue it is the right thing to do for the kids