I have a few questions… what kind of attention is it that you want?  Check out the “love languages.” Sometimes it’s a specific thing that we want or a combination, and reading about those things can be helpful to both narrow down what you’re looking for AND you can then let your partner know what you need in a relationship and can see if he will be able to give you those things. He can also figure out what his love language is as well.

The next thing… why is he so tired? Is he working a lot or weird hours? Does he have an illness?

I think it’s fairly normal for relationships to cool off after a time when hormone levels return to normal (they’re generally higher in new relationships) and people settle into a daily routine, but it’s possible you two aren’t as romantically compatible as you initially thought OR it’s possible that he’s just really tired for a reason and it’s affecting his life in a lot of different ways. I think it’d be a good start to be direct with him about the kind of attention that you need, with him seeing if he can provide that for you. If he can’t or it’s too much for him to keep up with, that doesn’t mean there’s anything necessarily wrong with him, it just might be that he’s not your match.