This is where you need to value yourself over the friendship. What you've described is pretty much unacceptable. I would just go home, get an Uber, just walk, whatever.

That kind of behaviour is completely unacceptable, no matter how much you care about her.

Address the situation directly with her, if it ends things, then so be it, you will be better off alone than being made to feel like you don't belong by someone you care for.

There are other people out there who will value you and your time more.

hugs

Try not to be too pessimistic. I'm 30. I'm currently making new friends left and right. Something which my previous therapist said was basically impossible. Find a better group. Hell, become a furry. No, seriously. Furries are cool people and eventually you'll find one who's a "connector" aka "the person who seems to know everyone and hooks you up with the right people", and they'll help you out. That's been my experience so far. It took a little while, but eventually I stumbled across someone like that and it's been a lot of fun and I've been getting to know a lot of cool people.

Edit: oh yeah, I forgot to ask: have you tried just talking to her one-on-one to see if she realizes that you feel like you're getting left out? It may be that she didn't even realize she was doing that.

I think you still have a friend. But you should have more friends, so you're not so dependent on a single friend. If you have a rich menu of people you can spend time with, when one person isn't available, or not receptive, shouldn't be a big deal.

It is difficult to make friends as an adult, especially when you don't have any free time. If you're just sleeping, going to work, and eating. It's hard to find activities where new people are available. But it's worth it. Join a club, improv group, something that you actually get face to face interaction of people. And slowly add some friends to your roster.

It's never to late, to understand and then free your mind to get new friends.
Don't stay in a loop.

It's sad and hard,

She showed here color. It’s always sad to see a friend phase away but be found of the memories you have and maybe just take a break. If the friendship is hung up on constant communication to work maybe think of it in another way. This could be a great opportunity for you to reflect on the relationship and what you like about it and how you are viewed as a friend as well. And maybe you could find some new.