I have been with my SO for about 1 year now. I waited for so long for someone like him to come into my life. Our relationship is easy, loving, and very wonderful. 

Our one issue is his soon to be ex-wife. 

We met a year ago, and at the time he had been separated from her for over a year. He had married her after dating a few months (he felt necessity) and then he found out he was deploying overseas for a year, so married her bc he wanted her and his son and hers to be taken care of. So he bought her a car, they cosigned it, and he left. (BTW they had been previously married and divorced...thought they would try again. This was 2015) While he was deployed, only a few months in, she decided to cheat and told him she didn't want him anymore, got her name off the car, and stopped making payments. Moved in with another man and bought herself a mustang. (since this the car he bought her got repoed and auctioned and he owes a significant amount. its only in his name now and she refuses to help pay the owed amount)

He came back  (Sept '16) and moved into an apt. on his own and they started doing a week on week off with his son. I came into the pic Feb. 2017. 

They have had a slow filing of divorce...with me being proactive about it happening if he wants us to continue. He is a passive guy, so angry and pissed by what she has done to him that he would rather ignore it all. I have worked slowly with him that if our future wants to move forward, he has to be proactive in this divorce.

Well he deployed in January, and had her sign an agreement that was notarized for child support amount and that she would file taxes and deposit half to him.

She hasn't done this yet, she has received the money, and yet keeps coming up with excuses why she hasn't been able to deposit his half. 

Between slow lawyers working on this divorce, this damned vehicle in collections, and now her not giving him his taxes, she is just screwing with him and our future. 

What can I do? I am already trying to be be as supportive as possible without adding to his obvious stress from being deployed for the war in the sandbox and everything else on his shoulders. But I am so angry and hurt by everything this woman has done to him (there is SO MUCH MORE) and want to help but feel helpless with him there, me here, and just being the girlfriend.

I can't walk away. He really is my other half. I stayed single for so long, and really was quite picky. I am not desperate for a relationship, quite independent actually. I have never met someone that is for me, like he feels like. Our true only issue, is his "baby mama" and this damn divorce not getting finalized. 

Anyone have any help and advice on how to deal mentally, emotionally, and relationship wise with this?

thanks