What does it mean when your ex-girlfriend says "I miss you."?

My ex girlfriend dumped me about a month and a half ago randomly. She told me she needed a week break to "figure things out" well sure enough, a week later I find out that she slept with her ex boyfriend two days after she texted me she wanted a break. Her ex boyfriend has caused problems in are relationship in the past and this one definitely highlighted it. Anyway, I wanted to work things out, but she kept telling me she wanted to be single and that I deserve better. So we officially broke up then and after I would vaguely talk to her and try to go No Contact, but she'd still contact me. This happened for about a month and a half and she texted me yesterday that she "Misses me." What does she mean by this? Is she trying to boost her ego because she feels guilty about what she did and the break up or what? I also noticed a few days before, that she de-friended her ex boyfriend on Facebook, could this be part of the reason why she is saying this to me? The two days before this she has been trying to contact me by saying "hey, whats up?" and sending me a picture of her dog the following day, but I didn't respond to either of those. Could she be using "I miss you" to get be to respond to her? I really do love her still, as how horrible of a person she is and what she did to me. I do want to get back with her, but at the same time I'm afraid I'll be hurt again. I just don't know what to do and it's draining me.
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+1 y
So I just gave her a neutral response by saying "I know." Thoughts about my response?
What does it mean when your ex-girlfriend says "I miss you."?
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