Most unique case ever

I’ll make this as brief as possible. My husband walked out on me, our 3 1/2yr. old and (now) 17mo. old on 2/15/07. Nice timing, I know. He was having an affair which he denied of course. He had accepted a job with a private firm in Iraq as a Paramedic making 103K a year. We signed a property settlement agreement before he left, settling many issues. We had no intention of separating, we were going to try and work it out while he was away - let distance and time heal. He was left for Houston,TX to “process” for his job for 1wk 1/2 (during which his GRANDMOTHER flew his “lover” (married with 7yr old) down to be with him for three days. After leaving after a week and a half, he quit his job after two days in Iraq. He said because he left his life “a mess” and he missed our children. He “snuck” back in country March 31st and has seen our children 6 times since then. Now he’s taking me to court to modify the visitation schedule HE would not adhere to. He has been living frivilously off his 401K and now that he’s burnt through that, he just informed me he’s withdrawing his state retirement. (My lawyer said she’d put a “hold” on it - how long does this take? How long before he finds out we’ve done that?)
We live four hours away as he “set us up” in a house very similar to our old house in order that I could be close to my parents to help me with our children. I have tried getting jobs, but difficult with daycare/other things.
He has been living with his girlfriend, spending lots of money on her, her 7yr. old son, groceries, alcohol, eating out, etc. Meanwhile, my children and I are on welfare.
Please someone tell me there is a light at the end of this tunnel. He has pretty much gotten away with murder for a year, and my parents have spent every penny of their 401Ks trying to prevent us from being homeless. I’ve lost 60lbs in 8 months, and the majority of my hair.
Please please, someone give me hope. How much “hard evidence” will it take to nail him? He’s using his back as an excuse as to why he’s not working (he had minor ELECTIVE back surgery in early Sept.), but can go out and party, etc. etc. etc.
What will it take to prove his intentionally supressing his income, not caring about his children (spent 6000.00 in 35 days - none of which came to us - yes, we’re on welfare). He didn’t buy them birthday or Christmas cards or presents.
What can I expect in court when we go for visitation modification & child support? Do I have to bring my trunks of documentation & evidence, or will testimony do? I need help.