Modification of Support: Should I Petition for Modification of Support While Being Sued by My Ex

My question involves a child custody case from the State of: IL

My ex-husband and I share 50/50 custody of a 10 year old special needs child (physical and emotional special needs) and a gifted child. The children are in the same grade in school.

In 11/13 my ex-husband assaulted me, no blood or broken bones. I had a sprained wrist and some bruising. The police where I live treated me as if I were the criminal and declined to press charges. I had the police investigator come out the next day and he noted some bruising and swelling to my wrist. Since he didn't try to murder me I chalked it up to being a not-so-serious situation and got an OOP as the cop suggested. Getting the OOP was a terrible decision. My ex husband violated the OOP repeatedly with email after email and asking for the children to call him. Because of the holiday season I really did not want to see him go to jail, as this would destroy my children. We had a good relationship with adequate give and take until he moved in with his latest girlfriend, which is right around the time I remarried.

My ex stated that he never touched me and is now suing me for filing a false police report, a false OOP and attorney's fees, as well as filing a frivolous lawsuit. The police have not approached me at all about a "false police report". Obviously there's lots more backstory, including an OOP filed against me when I was out of state when we were first separated. Separately, he has, through his attorney, said that if I admit that the OOP was fraudulent, on the record, and pay $1000 toward attorney's fees, they will drop the case. I have no intention of dropping the case. I have done some preliminary research through the IL CS and it appears that my ex does not have much of a case and he cannot make a case for a frivolous lawsuit.

We now have a situation where it is time for a child support adjustment (he makes in the low six figures, I make low-70's) due at the end of January. I requested a custody re-evaluation in 11/13 because of our special needs child's increasing needs. We have no residential parent; my ex moved out of the school district and the children are going to school in my school district which will not change until they graduate from high school as part of our divorce decree. My ex travels frequently for work and the children come home to me, which makes me a default residential parent. This is something we need to do by decree, but I don't have any idea if I can after the GAL's report was delivered. :wallbang:

My question is: do I wait to file for the child support increase (with children at these stages, the expenses are staggering) and risk antagonizing him further, and wait until after the hearing hoping he drops it and file after the hearing 3/14? His attorney has subpoenaed the cop, the evidence tech, my children, the GAL appointed to the case, and me. Also, when I file for the child support increase do I need an attorney or is it just math that the judge can figure out?

I should add that I do not think the GAL did what I would expect from a GAL. The GAL was verbally aggressive with me, did not talk to the children's therapist nor physicians and asked in a hostile manner why I went out of state when my ex and I first separated. I did not mention his drinking, his pot usage, his emotional distance from me and our children during our marriage.

Thanking you in advance. I know this is a lot of information; I appreciate your time.