Should I stay or should I go? (Will things change after 6 years of dating?)

I have been with my high school sweetheart for 6 years now and he’s not ready to talk about marriage seriously. He’s still in the “party” phase of life whereas I am ready to get married and start a family soon. He’s also cheated on me in the past and I let it go and he lies to me a lot about what he’s doing. He’s also a heavy drinker. I’ve stayed with him in hopes that he would grow up and grow out of his ways but it doesn’t seem like that is going to happen. Should I stay and try to push through it hoping he will grow up soon or I should I just get on with my life?