Child support is determined by the net income of both parties. If your ex-wife has the ability to earn a living then you may be able to impute income to her- meaning a court may find that she is able to work and could earn a certain amount depending on her skills, etc.
However, you have to remember that if income is imputed to her, this means child support goes up since it's based upon both parent's income. One would have to run the numbers to see what the outcome could be.
Unfortunately, your expenses are not relevant to the amount of child support you pay. (in most cases)
Sometimes the new spouse's income could be considered when calculating child support, however, like mentioned above, it could have the same effect- the child support could go up and it's possible that you could pay more. Again, someone would have to run the numbers.
I don't know how your child support was calculated so I can not comment.
