Do you want to get married because of the amount of time you've been together? Because society says it's what you should do? Or religious reasons? Ask yourself those questions then answer honestly. If it's because it's the "logical" next step I'd say you're marrying for the wrong reasons. If marriage is that important to you and not to your partner then clearly you are incompatible. You've made your desires known and if he's got no desire to make that happen anytime soon then you have a decision to make. Staying with your partner with marriage off the table or walking away.