I would love to have 1 guitar that fulfilled all my needs. It would save a lot of time when it comes to maintenance, setup etc and I'd get time to get really comfortable playing it. So if that's how you feel about your guitar, I envy you. Don't worry about it, just enjoy it!
Presently I own an Ibanez 7 as my main, a Spanish nylon string (that I really like) for classical/ethnic/folk stuff, a cheap Luna superstrat for when I need a whammy, a Les Paul that I can't part with for sentimental value (and the fact that I've put x times as much money into it than it's worth), and a 5 string bass. I've got the Les Paul set up with high action so I can get a really raunchy sound when the song calls for it, that's pretty much the only thing I get from it that I can't get from the Ibanez. So yeah, each of my guitars fulfill a specific purpose and that's why I keep them. I have sold a few not because I didn't like them but because they did not fulfill their musical purpose with me.
Oh, forgot about my 12-string. It's junk really so it doesn't see much use. But if need be!