Are you not valued at your job? Even if your job is completely shitty, you're still serving a necessary function. If that's not doing it for you, do some volunteer work. I can guarantee you that your contribution to a worthy cause would be appreciated. Helping the poor, elderly or disadvantaged youth is pretty undeniable proof that you'd be valued by people.
With your current attitude, you don't sound like you'd be a very good partner, so I'd suggest working on other things to make you feel valued first.