If my boyfriend and I get married, will his child support increase? Can his ex go after my assets?

You and your boyfriend should have nothing to fear. That you have assets is generally irrelevant to their situation. That she has sole custody and he has visitation has no impact on the child support (I can discuss shared parenting as a potential impact but that does not sound like the case here). Child support is governed by statute and regulation. You can find the rules concerning it on line. Simply follow this link. http://www.jud.ct.gov/Publications/ChildSupport/CSguidelines.pdf The only exception to the general rule that a significant other's income or assets don't count is in the deviation section (page 23 of the booklet). I think his worst case scenario is that he will be wasting his time and possibly have to hire an attorney to defend against her future motions. I can help him or refer him to someone more local should you need it.

Unless you are applying to become a legal party to the custody of the child(ren) in question, your boyfriend's ex has no business bothering you. You are not responsible for your boyfriend's custodial/support matters. Feel confident in not divulging any information about yourself to her and in ignoring any of her attempts to involve you.