5chatzi, I'm sorry you're feeling so upset about this change in your friendship with this young woman.

It does sound like you have developed a strong attachment to her, or at least the idea of her (I'm not sure, did you actually meet in real life?), and it sounds like she is trying to establish new boundaries in your friendship which has been a shock to you.

Taking some positives from what you write it sounds like you were a big support to her when she was struggling, and from what you write it sounds like she values your friendship. This might be something you can comfort yourself with.

IMO you need to decide whether contact with her is in your best interests given your intense feelings. Is hearing from her causing you more harm than good? Even if just temporary a break may be needed so you can get some 'head space'.

Long term if you are feeling like you don't have enough real life friends, and you are feeling isolated then that is something you can start to do something about too.