So your step daughter's mother is SELFISH.....I encourage you to stay a "friend" of your step daughter.....only if to help her be able to learn what MARRIAGE REALLY IS....COMMITTMENT!
These are the issues that to me can be really hypocritical.
Commitment..
I lived next to some people about 12 uears ago, I was single at the time and I would always talk to them it so happens the *Husband* would come over to my house and at first it was nice and friendly, then he started to pur his heart out and tell me that he was totally *Committed* to his wife that he was a devout catholic and would not divorce BUT his wife no longer was interested in sex and he wanted to see if I would help him out so to speak???