Well - first of all, be careful about dating and living with him if he's abusive. Don't let it escalate, you need to get out of there asap.
As for what you might get in the divorce - it matters a lot which state you live in. Are you in a community property state? Do you have any property to divide? Are there any retirement funds to be considered?
Do you own a home? Do you want to stay in the home? Can you afford to stay in the home?
Typically, after 15 years of marriage, you would get 7 1/2 years of alimony. (This isn't set in stone, but seems to be the guideline in many states - half the length of the marriage). And child support, if you get primary custody of your child. Ideally, everything else that was acquired during the course of the marriage would be divided evenly, but if you're not in a community property state, that may not hold. (Debts would normally also be divided - if you have a lot of debt, ideally you would like him to take that so it doesn't drag you down in the future. You might have to trade off for some future benefit like house equity or pension).
How does his offer compare with this? What are you differing on?
I know I could have gotten more if I'd gone to court - MAYBE. There was one issue which could have gone either way, depending on the judge - a rather big issue. I opted to compromise and get it done without going that route. I'm satisfied that my settlement is good enough for me, and reasonably fair - the ex thinks he got screwed and I think I did, so it probably IS a fair settlement!
Don't undervalue the years you spent as a SAHM though. Imagine what you would be making if you had focused on your career all those years and HE had stayed home?
