Hey,
I think your friend has made it pretty clear what level of relationship he wants from you. He wants to be friends, but nothing more. From what he's said about doing your own thing over the summer, it sounds like he's feeling a little swamped as well.
I think as Aspies, when we find someone we like, we want to spend all our time with them, and that can be overwhelming for the other person.
I would suggest that over the summer you find some other things to do, hang out with some of your other friends etc etc. Try not to 'put all your eggs in one basket' so to speak.
And just to let you know, I have done exactly the same thing in the past.
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If you don't believe in dragons it is curiously true, that the dragons you disparage choose to not believe in you.