You aren't married yet. Three spoiled little girls grow up to be three entitled adults who will always remind you that you are an outsider, second helpings, and daddy loves us first three times over.

They will always be there, they are never going away. If they do cause mommie dearest shapes them to be alienated your DH will be resentful that he has lost his baby girls. Chances are he wont want more kids. OR he could be like my ex DH who said he wanted more and marries you then changes his mind. I am bioless and that ship has sailed.

Many will advise to be open in communication make certain you are on the same page. Which is dang good advice BUT all too often all you will have is heart ache after heartache. A constant reminder you are last on his list.

You are already unhappy with THREE SD's. Save yourself and find someone else.

To answer your question from my experience it is NOT worth it

I'm with Gimlet, she said it all.  In your case, no - it's not worth it. I hung in with my DH because he was a good parent and I liked my SS, and BM didn't target me.  If BM had targeted me or turned SS against me, or if DH had been a guilty parent - we would not have made it.

Steptalk is the place for you.  Many people here have your exact problems and you can learn a lot from reading through it.

You ask, "Is it worth it?"  As everyone is saying, you are up against huge obstacles.  Do you enjoy being with your SO so much that you are willing to put up with it all?  Thats the core question.  If your answer is yes, then find an excellent counselor and enter therapy.  Look for one with experience with step families.  Good luck.

To answer your question: No, it's not worth it.

He brings a lot more baggage into this relationship than you do.  One bratty SD would be enough to end many relationships, three is way too many.  Add the HCBM, and that's a nightmare.

You are unencumbered by baggage and free to live a happy life with a childless man.

If you stay in this relationship, twenty years from now you will wonder why you squandered your youth on this situation.

I've been in the game for 25 years including a mini-wife on steroids. No it isn't worth it. I ended up with a form of PTSD from one spoiled girl never mind three. To answer your question if a girl as young as 9 can manipulate and create havoc the answer is absolutely.  My SD was 7 and you wouldn't believe what she had pulled off at 7. 

There are so many red flags in your post. Spoiled girls leads to enmeshment because Dad can't say no due to guilt over the split or fear of losing them to Mum's influence. Also, there's something about girls that makes these types of dads very weak and cowardly. The girls will always be above you and will ramp up the manipulations. Don't count down until 18 for them to launch. Spoiled SKs do not launch or meet any other milestones when their peers do. If they seem even a little behind to you take that as a sign that they are being kept young by their parents so they can never leave. Go read the adult forums about SMs who have 32 year old SDs still living with Daddy and the SM is left with the choice to either put up with it or end her marriage.

Your BF is feeding you a line to keep you hooked. If he was doing everything he can to work towards marriage with you he would be divorced by now and he would push for it and not fear rocking the boat. 

My SD is 31 and the clingiest cling-on for DH I've ever seen. She keeps all of her forms of communication open 24/7 to constantly contact DH. DH is a lot better these days but we couldn't even watch a movie together without DH having his laptop in his lap because of SD needing constant contact with DH.

Not a day goes by that I don't regret marrying a man with a spoiled bitch. I had the same physical reaction you described whenever that c*nt was at our house on a mum's night. When SD was older and driving I'd see her car from down the street and I'd immediately turn around and drive to a secluded place to scream my guts out and bang on the steering wheel. I have never in my life hated someone as much as I hate her. I hate her even more than the person who beat my head in and left me for dead. Seriously.

I fantasize every day about running away and becoming a cat lady. DH and I have had a ton of therapy but the damage that was done still over powers me and every day I think about throwing in the towel on my marriage.

No it's not worth it at all. If you have kids they will be second rate next to your SDs. My DD20 ended up in therapy by the time she was 15 or 16 because of it. SS29 rarely contacts the family because he's a distant second to SD and he has to protect his fiancée because SD manipulates so much that she's destroyed three of SS' past relationships. He found a keeper so in order to keep his lovely fiancée in his life he has to keep a distance to protect his relationship. 

Run fast and run far.

Agree with everyone but I also want to cast my vote on not worthy.

BM saying crap about you is a pretty shitty thing to do, however it's also understandable that 1) her girls of course will side with their mom 2) since he's not yet divorced who knows what's going on in their relationship.

Guy has too many baggages, does he have time for you?

NO!

If you are staying in this relationship with the hopes their will be a light at the end of the tunnel. You are fooling yourself.

As everyone pointed out, the red flags are their to predict a bleak future for you and your SKs..

If you still think this man is worth it. Be prepared for years of drama and dysfunction from BM and SKs. It's not going to get better.

I can't really add anything, there's been some great advice that I would echo.  I only have one SD who is grown up (don't think it all ends when they're older) but three girls - wow that is rough!  Save yourself x