1. You deserve to feel special
If you want something, and you're wasting your energy on waiting around or trying to reason with your "man" why he should commit to you, you certainly are not giving yourself the self worth that you deserve. You are a gem, and any man would be lucky to have you as his own. If he cannot see that, then he doesn't deserve to be with you. While he wastes your time with BS excuses, and enjoying your company, there are men out there that will want to sweep you off your feet.
2. If you have to force him to commit it won't last
Simple. If you try to make someone do something that they truly don't want to do, nor believe in then it isn't genuine and most likely won't last. Think about the following difference, if you asked someone; "do you love me", and they respond with "yeah", versus them taking initiative and saying "I love you!"...
3. Life is short
At the end of the day, no one is getting any younger. Don't waste your time and efforts. If he doesn't know what he has, and doesn't see you as someone worth taking off the market, then maybe he should find someone else.