Hang in there! I went through a similar situation with my son. I live in PA but my family was in MO, and when we split up, I wanted to move closer to home. So he filed for custody. We wound up working it out in mediation and never had to go to court. (Although, he wouldn't settle anything until the mandatory psychologists report came back, I firmly believe that in the back of his mind he thought I was crazy because I didn't want to be with him) We've actually been able to develop a friendship over the past 7 years. He even admits now that custody was never his intended outcome, he just wanted to make sure I couldn't move that far away and take his son. It has worked out to be a very amicable situation and our son is the one who benefits the most from it! (And yes, his mother is unbearable, but at least she lives in another state)
Just make sure you keep a positive perspective. You can turn a bad situation into one that works for everyone, especially you! You will be surprised at how much strength lies within you! And being a strong, independent woman who isn't a pushover sets a good example for your son, trust me! And for the record, at the time of dispute I had moved with my son into a 2 room apt. and my ex made 4x what I did, but I still was granted primary custody. Your son is young, he needs to be with his mother. Period.
Feel free to PM me anytime.
"The bicycle is just as good company as most husbands and, when it gets old and shabby, a woman can dispose of it and get a new one without shocking the entire community." -- Ann Strong, Minneapolis Tribune, 1895