<human>: Can you give me the gist of the text in a nutshell?

Im an 18 year old male. In July, I met this girl and she really blew me off of my feet. I knew since I met her that she would be mine.

Prior to meeting me, she had a year and a half relationship end in May. Now me and her began talking in July, and in August her ex boyfriend tried to get back with her. Fortunately she chose me, and me and her have been extremely happy until recently. 

November would have been her and her exs two year anniversary, and recently she told me that it has been bothering her. She tells me, "a lot of things remind me of him" and stuff like that, and that it's hard sometimes. That she didn't really get a lot of time to heal from between she broke up with him and met me. Also, her ex still has all of the pictures of them up on social media accounts. I told her that if I'm laying with her and she wishes I was him, then to end it because I don't want to be a rebound. She told me this was not the case, but she has a hard time explaining things because I feel as if she's holding back her feelings to preserve mine. 

Since she told me, things have been a little weird, and a lot of times I could tell something is bothering her. Sometimes we are normal and like we were but other times it just feels as if somethings not right. I feel as though it's just a phase since she tells me she had forgot about him until what would've been the second anniversary and things just hit her. I told her I understand, because I feel as though it's understandable but at the same time I just want to fix things.

She is my happiness at this point, and she's out of my league. I don't want to leave her.

I guess my question is, what do I do?
<bot>: Me and my girlfriend have been great until recently, when what would've been her and her exs 2 year has her thinking about him again. I don't know what to do.