My ex boyfriend added me on facebook?

We broke up a month ago, but in that time frame we were talking constantly.. finally I decided to let it go, because he was saying that he didn't want to be with me.. ( I broke up with him). I sent him a letter saying that I agreed with his decision and that same week he added me back as a friend. (we didn't talk for a week). he still has our pictures up, and he posted a couple days ago that he was "thinkin.." lately his posts have seemed depressing... I want him back but what the heck does this stuff mean?
My ex boyfriend added me on facebook?
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