spousal support

I was married for 21 years, I am currently 51 years old. I have 3 kids, the youngest is 17 living with me. The other 2 are on their own. We have been going to court for over 2 years. Only had one case conference, which is was asking for custody of our then 16-year-old daughter, which he only sees a handful of times all year. The children’s lawyer got involved and delayed everything for another year. Meantime, he has been reducing his income significantly, which is why he wanted the children’s lawyer to get involved. My daughter does NOT want to live with him under any circumstances. He refuses to have to pay spousal support. He made 3 times as much as me 5 years ago and now makes less than twice as much. He was paying me spousal support in the beginning, but not as much as he should have been. He would not produce his NOA’s, because he hadn’t done his taxes for 3 years. I finally got a lawyer and forced him to do his taxes. He made a lot more than he had claimed to be making and now owes me back support. He stopped paying spousal (which was half of what he should have been paying according to SSAG) because my boyfriend lived with me for less than a year. I am not with that boyfriend anymore and we are still fighting in court over spousal support. I did not work for 15 years of the 21-year marriage to raise my children. We had nothing to split between us. I left him with the house, that had no equity in it, and bought my own house. I saved my money and with the help of my parents managed a downpayment. He still doesn’t see my daughter but maybe once a month. Both my other kids don’t really see him much either. One of them will not acknowledge him unless they are at a family function, and the other sees him once in a while. Is it worth it to fight for spousal support? He is in arrears for 5 years for some child support and now for spousal as well. He refuses to negotiate at all.