As I plow through the fat the meat of the matter is this. He wants to move to be with gf. Well, I think tha t is pretty pathetic on his part. he has a kid so the damn gf should move to NY.
Job: I think you are making some excuses. No offense but you are very young. Jobs aren't going to knock on your door and you are going to have to work...there is simply no choice so just accept that.
Child support...don't get me started. I believe in shared parenting. If that is feasible here and you both share in everything then why does he need to pay you support...he works, you need to work...now, it would be very reasonable for him to pay for day care. However, if he has care in Mass and you in NY, and you both share equally (or pretty close) then should you each not take care of your own expenses.
He is 36 and has a trade, job, maybe education. If you are 23, and the kid is 2 1/2, then you were 19 right out of high school when you got pregnant. my dear, what are you thinking of in the way of the future? School? trade school? What job? Do you have family near by?
There is a bigger picture here than child support. There needs to be a larger support structure. I would suggest that you come to an agreement that is fair and equitable and put it into writing. based on what you have now may I suggest one of you take Monday and tuesday over night, the other Wed and Thursday overnight, then alternate weekends. That is a 50-50 plan. If you need money then make hime pay you in accordance with the typical rule, 20% of net income (net is after FICA, taxes). However, you would have to pay for day care out of that. If he wants to move fine..but then he needs to pay for his care also.
lay out the plan. Put it in writing. Make him stick to it. If he does not show up document it. You have to get your life in order as well. Don't count on others...make it happen for yourself. You have your whole life so if you have to go to school part time to make a better life for yours and his kids do it...