5) to keep things civil. Maybe he doesn't want to feel guilty, maybe you have to see each other regularly and he realises that you'll need to learn how to get on platonically. (I guess this is less common though). 6) maybe he's simply checking up on you (quite common).7) maybe you spent a lot of time together and he's finding it difficult to adjust to life without you - although this doesn't always mean he wants you back - it can meant that he's just used to having you in his life through a force of habit.It could be a mixture any of these. It really depends on the guy and what kind of relationship you shared - but I'm sure you'll be able to have a rough idea based on your own knowledge :) I hope I maybe helped a little.
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