I'm divorced in NYC. I'm paying for my daughters college fee. Does my ex wife refuse to help?

Assuming there's a court order that requires you both to split the cost of college tuition equally, if she's not paying her share, you can take your ex-wife to court for violating the order. If you win, you may get reimbursement in the form of a credit toward your child support payments, or the court may order her to reimburse you in a lump sum.