Yikes Julie!
I believe if something with a friend or lover does not work out then it’s for the best. It seems that this was with your entire friend group. That sucks for sure. Such a big loss is like a death. You are in a grief process where betrayal, anger, depression and other such feelings come up with a loss.
You can move on, make other friends when you are up to it. One common receipt for getting out of one’s self, depression and loneliness is to volunteer and help others. We have Meetups here where we can do fun activities in a group.
Take care of yourself.
Mark