I think that you just have to decide what your boundaries are. Everyone has a different idea about how to live their life. You might not agree with their choices but they get to make them. You also get to protect yourself by recognizing what you can and can't control. If you want to send the occasional trinket to your grandchild then do so, if attending the social affairs isn't your cup of tea feel free to bow out. The point is you get to decide how involved you want to be in their lives and remember, expectations are just premeditated resentment.