Girls, Recently I got into a long distance relationship (700km) and she is very pessimistic, how do I help her and make her see that it will work out?

She even started doubting our relationship but she does love me, wants to be with me and even loved the idea of moving in together. She is currently in university, 1 year till graduating.

It has been hard lately for me trying to help her and I am out of ideas and now I am confused and lost. We really want to be together but she changes her mind quickly and thinks too negatively.

I will be visiting her soon, so I need all the help I can get haha, I really care about her. I know what she is going through, university, self doubt, tired all the time, etc.

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It didn't work out, she just used me and played with my feelings, so she feels better about herself and found someone else to use while we were still talking.
Girls, Recently I got into a long distance relationship (700km) and she is very pessimistic, how do I help her and make her see that it will work out?
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