Looking for a song, can't find it.. Please help?

[Bube]

I heard an old song I liked, but don't know the name. I even did a lyrics search, but it didn't turn up any results. Here's the part I remember:
I belong to you, and you belong to me too.
You make my life complete, you make me feel so sweet.

Oh, and there's another song I don't know anything about, but I'll give it a shot. There's a male and a female voice, and they say something like "what comes around (round)". It's a slow pop kinda song.

Please, if anybody knows the songs, and posts their names, I'd be very happy.

Man, I feel so stupid. I hate singing in front of others, and right now, I feel like I am...