divorce but got screw by ex

[wesley67]

Recent i got the main care and control of my kids but my ex wife pay upfront of the feb busfare. she demand that the money to pay back.
what else can I do if she demand any other forms of money that spend on the kids.
we went counselling by court order, my ex wife husband claim that my father threated to beat him up in the past so the Counselor was acted on behalf of my ex wife she don't want any of my father, me and my mom to fetch or send her back to TPY.
The counseller advise us only my sister or other relative allow to fetch or sending her back to Toa payoh.
I don't wish to get my relative to go through all these.
she remarried a richman and got a son, because I can't afford a luxury lifestyle for her.
when my marriage failed, my whole life was crumbling down.
I got no one to turns to except my both kids.

1) About income Tax relief she take it all. can I take relief also?
2) maintaince,sharing to cost of my kids or is just me alone bear the cost?
3) I think my ex trying to use 3nd party to sabotage me. that why my sis was involved. how to counter?
any brother can share experince of what else can this bitch do?