Take you money out of the relationship and let DH pay for his son ... and for you....

simply put in boundaries and rules, tell DH, SS will have to find a job and pay rent, or pull his weight and do some house work during the day when you both work.... or SS is out... give him 3 months to comply, (I always work in 3 months I have no clue why lol)

and make it clear if SS does not ship up he ships out, or you will.... after 1 month DH will feel his wallet getting thinner and thinner, cause you will open your own bank account and not pay towards house hold expenses, only about 25%
It's 4 adults in the house.... it's 25% per person. Include the GF, she will stop coming over.

If your name is on the deed of the house you have as much say as DH, if it's only your house then DH has no say, you simply kick the adult baby out.... if your name is not on the deed 3 months is enough to find your own little flat, privacy and then you contribute nothing towards DH's house..... yes living apart can work.

Yes you love your DH. However loving someone does not mean you HAVE to live with them in a toxic cesspool of laziness. You married DH not his son. Start with restricting your contribution to 1/3. Then in 1 month if GF is there more often than not reduce your contribution to 1/4.

Tell DH that his son needs to get his own place so he can run his own life. If DH says he will never throw out his son (big grandiose gesture of passive aggressiveness)just ask him is he prepared to lose his wife for the comfort of his son? Is he prepared to have his son living with him for the rest of his life? If he thinks this is OK you've got your answer.

SS doesn't 'win'. DH loses because he loses another partner. You win because you get to conduct your life as you see fit. I know this is tough but making a stand and keeping strong will show you what DH is really made of.

One thing that worked for us was changing the locks and not giving SS a key. When he failed to do his daily chore bitch duties he was left on the front step when we left for work.

Give it a try.

My guess he will ask for a ride to the recruiters within a few short days of spending the day without food or water on the front step all day. This was when my SS learned the joy that every kid back in the day knew instinctively. That green thing coiled next to the house spits out water when you turn the faucet on.

Absolutely agree with Rags.

I'll assume you are on the House note OR lease, correct?

So, it's also your home, correct?

Don't put your hard earned money into the Mortgage, give 1/3th of the light bill to DH to pay your portion. When ss gf comes over only give 1/4 of the house note to DH with a receipt.

Same goes for water, electric, cable. ONLY pay your portion depending on the amount of people squatting there.

Here we go again with parents not expecting adult kids to stand on their own two feet. Did dad always have custody OR was it once child support stopped all of a sudden ss wanted a relationship with dad?

That typically how it is UNLESS pathogenic parenting is at the helm then kids stay away until totally away from the bm. Sometimes those relationships are never healed, ever.

I agree with all of the posters who suggest separating finances and paying 1/3 or 1/4 of all household expenses (depending on GF. I experienced this very thing.

When I was paying 1/2 of everything DH would puff out his chest, be the big man and pay for everything - including depositing hundreds of dollars into SD's back account every month. At the time SD was making more than DH was but the 'show' was worth it the ego boost for him.

After I suggested DH pay for his family expenses and I pay for mine, DH's generosity diminished significantly. A residual affect of this, and something to keep in mind if you want to delay separating finances, is that the money that should have been saved for DH's retirement was placed in SD's bank account. Now that DH is retired he is walking a fine line - I am hoping nothing serious presents itself to him because I am 100% sure that SD would not bail him out.