Your boyfriend is not committed to you. You can feel it. Maybe he says you're wrong but there are just too many things that suggest that what you're feeling has merit. He never talks about the future, he doesn't introduce you as his girlfriend and he freezes up anytime anyone talks about a wedding or marriage. Deep down inside you know that the relationship isn't going in the direction you want it to but you don't know what to do to change it. You're worried that you're going to have to spend the next few years of your life waiting for him to see the treasure he has in you so he'll get more serious about you.
Before you can change your boyfriend's desire to commit you need to figure out why he's holding back. There are a whole slew of reasons behind why some men are reluctant to commit. It can run the gamut from just not being ready to actually being fearful because they went through a difficult and painful divorce situation as children. Consider all of his varied reactions to your discussions about commitment. If he says he'll never get serious because he's too young, you know that it's a maturity issue. If he seems pained when he speaks of his parents' divorce, you know that he's fearful of the same thing happening to him. You need to take some time to really think about what you believe is causing him to not commit.
Getting a man to commit is all about making him believe that it's his idea. If you push him into it, he'll push back mainly because he wants to take the lead. That's why it's essential that you don't put pressure on him by talking about how much you wish for a commitment or how desperately you want him to be all yours. If you've mentioned it even once to him, that's enough. He knows that you want it so there's no reason to repeat yourself.
Playing hard to get may seem ridiculous when you've been with a man for a time but it can prove very helpful at any stage of a relationship. How it works in relation to getting a commitment is quite simple. Stop acting like his committed partner before you have that commitment in place. If you tend to all his needs and make yourself available whenever he wants it, he'll see no reason to change even one thing about the dynamic of your relationship. Stop playing that role until he suggests you two actually do commit to one another. That means you worry more about you than him and don't spend every waking moment thinking about what you can do please him. Life your life for you and he'll start to see that having you as a partner is what he really wants.