I have no idea whats going on or what to do; thoughts?

Here is the story:

I met a girl one year ago who is 8 years younger than me. We met because I have been going back to university to get another degree and she is in my program. At that time I had been about a year out of a long term serious relationship, and dating wasn't something I was not actively pursuing, I was just happy to go to school.

But - she kept talking to me, and sure I thought she was cute so I was happy to. We started studying together all the time and she gave me her phone number (I never asked). With this we talked more and more as the year went on; later and later into the night too. By the end of the year we would meet about once a week for coffee or beer just to hang out - and it was fun. I really started to like her, and she would tell me that she was thinking of me a lot too. We started texting each other late into the night, every night. By the end I would wake up to a text from her every day. We flirted constantly. She almost always initiated texting. We never talked about it openly.. but she definitely had some sort of issue with an ex that bothered her.

The end of the year came, I had a work placement in another province and I had to leave. We talked about what we were going to do in terms of contact over the summer.. she admitted to having feelings for me, but said she wasn't ready for a relationship plus I was leaving anyway. We agreed to try seeing each other in the fall. I gave her something of mine to hold on to for the summer, it was romantic and it really made her happy.

We gradually talked less and less over the summer. I thought of her a bit, but had no idea whether or not she moved on. It made me sad to think about that. I wasn't in a position to move on with other girls because I lived in a remote area, so I just lingered. Sometimes, when I would text her to ask her something innocuous, she would flat out ignore it.. or she would start talking to me at night about something like buying a car and she would abruptly stop talking ignoring pretty basic questions - nothing heavy. It hurt to have that happen. Overall, she would text me about every two weeks asking if I am alright etc etc.

Two weeks before school, to my delight, she started ramping things up and brought up that she would like to see me, and had kept my thing as reminder of me.

Once back, we met almost everyday, she started coming over to my place during the evenings. We texted late at night daily, even straight to dawn once. We texted some heavy sexual stuff too. If she went out drinking, she would drunk text or call every time. She thought about inviting me to meet her parents 2 weeks ago, but got scared. When she came over we would cuddle, I would rub her back or feet and I would kiss her forehead, that kind of stuff. But - I never really felt she was comfortable enough for me to try anything more as of then.. Throughout all of this we talked openly about 'us' and our pasts.. like if we should see each other more intimately or not - she always started these. I never got a straight answer, except that she doesn't care about the age gap but kinda likes it - which I think is exceptional. But as far as what we do: it was always 'I don't know'. But she has talked to me to all her friends and her parents and apparently from, what they hear, they like me.

Here is the bad stuff: she was really hesitant because she apparently still loves her ex. she has been back and forth half a dozen times with him over the last 2 and a half years. he was her first and they lived together for a year out of high school and were together for 4 years. She wants to move on, however, she told me one time, she had great relationship with a guy that lasted months, no problems - until her ex (from out of town) just showed up out of the blue and she left with him on the spot, breaking this poor guys heart. Now she finds it difficult because they can't talk anymore, and does not want that to happen to us. I also found out she got back together with her ex over summer when she was ignoring me, but it ended quickly. None of her friends or family like this ex, they think he treats her bad.

My problem: Everything was going fine for us, until her ex found out we were hanging out and had begun trying to get her to come out and see him. So far she hasn't - but know everything is weird between us.

I have really fallen for this girl. We know so much about each other, and we make each other really happy. But - I don't want to do all the emotional heavy lifting for her all year, and have her go back to her ex for sex or to otherwise have a more physical relationship - again. I sort of expressed that to her one night, and now we are not talking very much at all and its stressful for both of us as we still have to see each other everyday at school.

I really want to see her more again, she is really fun to hang out with, and we do keep each other during all stress of school. She really wants me to keep talking with her too, in case maybe, something can happen. But she wants to figure this ex thing out first before we can be a couple. I just don't see that that could happen unless she actually tries to be with me.

Things are breaking down. She will talk to me about once a day now, shortly, never at night somewhat flirty, but she will ignore me again. I almost think that she is talking to her ex in this time now, but don't know for sure. One red flag is that she went out drinking and for the first time in a while, didn't drunk text me.

Should I keep trying to talk with her?? Or would I be at risk of being hurt over summer again if I do, but worse this time. But I also don't have a lot of chances with younger, cute and very pleasant young girls like this - I kinda don't want to screw this up if I can help it. And I do care about her, I don't want this guy to hurt her again.

If not, how should I deal with her at school? Like feelings come back really fast when were together, but I don't want to be a big dink and ignore her flat out.

I feel like fixing this is probably not going to happen and I need a good exit strategy.

Any advice?