Ex came back around for birthday

So me (34m) and my ex (30f) broke up in June over some family issues with my daughter from a previous relationship. We’ve been no contact the last 6 weeks and she called me on my birthday (I know). It went great honestly she was excited to speak to me and as was I. Shes almost done with RN school in 4 weeks and mentioned we should get together after she finishes. So we text for a good part of the day and later that night she mentions coming to see her at her job and I’m soft so I did. We sat in my car for about 2 hrs (she works 3rd shift so no one cared) it was great we talked and made out a little like teenagers. We talked about how much we missed each other and the dating scene etc. Then the next day she was so excited about how everything went hot and heavy texts etc and she can’t wait to see me in December. Later that day she says it’s not fair we’re not together and she mentioned she misses me blah blah blah. So the next day comes and she’s kind of quiet so I knew something was coming. She starts with “I truly think we will have each others hearts forever even if we don’t work out” She said she told herself she didn’t want to talk to me until school was over and she feels guilty talking to me because the feeling of it might not work out and maybe this chapter already closed. And btw she is bipolar but I’m not gonna lean on that too hard because I wanna see what you guys think of it all. I feel pretty crazy today it’s been a roller coaster and feel drug through the mud. I guess I shouldn’t have agreed to anything honestly. The love is there but the certainty is not. I guess I don’t really know what I’m doing and prob just a doormat at this point. Thanks for reading.