That sounds like a hard situation. I can totally understand how you're feeling, I too have very strong abandonment issues and would probably feel similar to the way you're doing right now in your situation. Remember that while your therapist didn't do anything wrong, you are still allowed to feel all the things you're feeling. She was an important person to you, and grief about the 'loss' is a very normal reaction. And since you're probably not yet at the point where your issues are resolved, your feelings might seem over the top to others or even yourself, but given your problems, it is normal to feel that way. I haven't personally gone through this with my therapist, but I have with other important people in my life, and my reaction was very similar. Lots of different strong emotions, feeling horrible, going back to bad coping skills... I've also read of many people on here who had similar experiences with therapists, I hope some of them will reply to you as well!

I think it's good you have someone to talk to, even if it's just a temporary therapist. If you feel up to hanging out with your new friend group, that sounds like a healthy coping skill as well. It's okay if you don't feel completely the same as usual, it happens to all of us sometimes and it's still nice to know people are around you that care. I've also heard of some people who had good experiences with setting away a specific time each week (for example if possible your old session time) and in that time allow yourself to mourn the loss, think of what you've experienced and so on. I'm also sure you're always allowed to post on this forum and talk to people on here if that helps you. For me personally, I'd probably find comfort in things that remind my of my T, but if that feels too painful, avoiding it for now is okay as well.

I know right now it sounds impossible, but given some time, the feelings will lose some of their strength and you'll hopefully also be able to remember the nice feelings and memories that you have of therapy with her, but also experience similar things with new people.