hi
you certainly do things you wouldn't normally do when you are manic. and things feel sooooo different when you are manic - so things like love are really intense. You wont get the same intensity that there was during the mania in other mood states.
But was it "just" the mania???? I think that often what you feel in mania is an amplified version of what you normally feel - but not always, sometimes its just plain crazy, so it is possible either way.
Remember that after a mania often comes a depression so if that's the case it could be the depression talking - it is hard to love in depression.
You can't change what he is feeling, you can be as supportive as you can - you should also think about who you love, it is him in all mood states or just when he is manic?
Best wishes with your relationship.