Cloud and Tifa were too "chummy" to be lovers. They grew up together. Tifa was prettymuch a guy to Cloud. She wasn't dainty or delicate, like Aeris. She was manly and buff. I think that she may have had some kind of crush on him, though. She said all that stuff about wanting her hero to come save her. But as they grew up, they seem to have grown into more mature friends, and ditched off the childish teenage crushes they held onto before.

I don't know about Cloud and Aeris being in love, either. Though it certainly seems like it. His compensation for protecting her is that she has to go out with him. And there's other things I can't recall that suggest the idea.

Truthfully, I was kinda hoping that Cloud would end up with Barret. That would be hot.