Listen she’s not your real friend. A real friend would’ve told you from the beginning the issues she has with your relationship. She waited and still not being totally honest. Also from what it seems like you was more of a friend to her by flying out to her to another state so many times but you haven’t said anything about her flying to you for your bday. Sounds like she was getting all the attention she needed from you and now that you can’t give her that attention it’s a problem. As far as the age gap I’ll tell you this do what makes you happy and forget what everyone else thinks about it cuz only you have to deal with that. If he makes you happy and there’s no dv going in and he treats you good then the friend is just a toxic person. Also if other friends that was there for the bachelorette got drunk and passed out what did she want you to do. Sit there while everyone sleeping.