I know this example will sound horrible/unwise, but here it is.

I've had girlfriends without having the capacity to love. I never told any of them that I couldn't love them because I couldn't feel emotions. For two of them perhaps I should have and was just too much of a wuss, but for one of them our whole relationship was basically fine and I would have broken her heart to tell her, and even though I had a hard time feeling emotions and love I wanted to keep her as a girlfriend. We eventually separated for other reasons, and I like the way it worked out. I'm glad I never told her. =P