If you're not sure .. then don't do it. Maybe you two need to take a break and see if you really feel the same about each other anymore. I have a feeling you might still doubt his commitment to your relationship .. no matter what he's saying now. Probably a good idea to be cautious.
My observation ... you only have so many years in your life.<br />
If you want to get married, have kids and the rest, every year you spend with this guy is one less year that you'll have being happily married.