I don't know about happiness, but you get use to it.I know because I am an isolationist. I don't do well around people. My anxiety and my socialphobia kick in and I half to go to my room because it is the only place I feel safe. Sure the first couple of years I wondered if I would ever feel happy again. With time that all fades away and you accept the fact that this is what your life consists of so get use to it.
My therapist told me to get a puppy. She said there love is unconditional, and it gives you someone that relys on you to train them, and play with them, feed them, take them for walks... yes I said walks. I walk him up the street and back. I do this early morning hours when there aren't to many people out.Good Luck:chopper: