I’m no expert, but if you’re having second thoughts about spending your entire life with him BEFORE you make a serious commitment like marriage, imagine how trapped you might feel [i]after[/i] you make that vow. Personally, I have followed my heart in every relationship I have been in, and I’ve never regretted the decisions it has led me to make. I broke up with my first boyfriend because I didn’t feel like he was ‘man’ enough for me, even though we did have a great relationship. However, the man I am currently dating feels much more right to me, and makes me happy that I broke up my last relationship to make room for him in my life. If i were you, I would go with my heart on this one.
I wish you the best of luck, and much happiness in the future!