Ex boyfriend blocking me on facebook?

[Katie]

So my ex boyfriend and I dated for around 2.5 - 3 years (something along them lines) and I broke up with him, and he quickly blocked me on facebook for a few months, then unblocked me when something was wrong with him - like relationship troubles (as he got into another relationship) and things going on with his family, then would tell me after a while he wants nothing to do with me, and I left it at that for around 4-5 months. Last week or two weeks ago, he announced he was having a baby and was going to be a father. He unblocked me the day he announced it on facebook. I know it may mean to get back at me for some reason, or to make sure I see it and i get hurt. But I want to see other people's opinions also, so what do you think of that? Thanks x