Look at it this way, there are men out there who WILL love you, but while you're wasting time with this one, you're not going to meet any others.
I know it's shit to realise that the person you love, doesn't love you, it really, really hurts, but staying in the hopes that he'll change, will be really bad for your self esteem. The longer it goes on, the worse you will feel.
Give yourself the chance to be happy, rip that plaster off. You deserve to be happy, and loved. Give yourself time to heal the wound before embarking on another relationship, and get out and about. Meet new people, find something that interests you, and find groups nearby for that interest.
Learn to love yourself, and your own company, and when you do, you'll be ready for the next chapter of your life. You're still young, make the most of it, you never know what's around the corner.