deadman... Selfish is ok, selfish is good. You have wasted how long being "selfless" in the work of the lord? You allowed yourself to be controlled by a cult but you are awake! At the end of the day, that is all that matters!
You have made bad decisions in the past but WE ALL HAVE! You treated your sister poorly but now you want to apologize for that. That is admirable. You want to have her and her family in your life now. That is normal. Do not be easily discouraged but take the advice of the many people that support you and make the decision that is best for your circumstances.
Good luck!
pbrow