How can I calm down and just see what happens?

So just to give some background this girl and I started talking for a few weeks last summer (we’re co workers) but she goes to school non locally so primarily it was over text and she suddenly lost interest in September with no explanation. The text simply said “sorry I’m not feeling this anymore”. And so she was home this past spring semester and we started talking again and I think things are going fine like we just made plans to go for coffee this weekend and stuff like that. But I can’t shake the fear that I’m gonna let myself fall for her as hard as I did last time only for her to just lose interest again when she has to go back in the fall. Now I acknowledge that things are different and we did talk through this already and she said “you just have to trust me. The last thing I want to do is to hurt you again. The main thing that makes this different is we have basically the summer to build upon this relationship this time as opposed to last year when we acknowledged that we had feelings she was already back to school

But even so I find myself reading into every little thing and it seems crazy even thinking about it now but I’ll get into my head and it’s just not good. But I also don’t want this issue to push her away.