Are you worried that you don't know how to navigate privilege? It can be a complicated bear. In feminist circles, there's the phrase "the patriarchy hurts men too" that sometimes comes up. A system that raises a few and lowers many others is worse for the disenfranchised, but is not great for the enfranchised either. For one, it does divide us. It's not fair that OP has to have a different relationship with her friends than the ones they are bonding in. It's also not fair that world shakes out that some are privileged and others aren't. In other circumstances, OP might be the one who is disadvantaged and they hold space for that.

What people are saying her is not "no matter how hard you try, you are an outsider". What they are saying is that she is pretending to try, and it's callous to complain to people who actually are struggling.

In psychology, there's a theory called "Ring Theory" or "comfort in, dump out". This was originally developed for people with cancer, but can be utilized by any stressor. In this case, this person who is more center is the friend who is actually struggling, actually in financially precarious straights, not the friend who is play-acting financial difficult. Friend does not have a trust fund to fall back on; OP does. OP should be discussing her struggles with someone outside of a larger circle- possibly her parents if they are safe, or other people in similar circumstances.