I need help with some advice about my relationship and my new friend...can anyone help me with some advice?

my boyfriends name is nick and we've been going out since Sept. and my new friend's namd is drew. we've been friends since june and well, now he's puttin the moves on me and i really like him almost in a relationship why. but what about nick. i mean yea, nick and i have 50/50 in common and dont always understand each other. we dont comunicate as well as me and drew do. but nick feels that he's so into me that he has already proposed to me (he wants to marry me!!!) and he's only 15. nick is 15 and almost 16, im 16 (33 more days till im 17), and drew is 18 and has his own appartment. drew is so much more machore and we comunicate much better, but he lives about 2 to 4 hours away distance relationship scares me a little but when im 18 i can move in with him) and he's 18...nick is 15 almost 16 (he's a year and a half younger than me), we dont totally comunicate that well, we dont have to much in common, and im just not sure about him anymore...what should i do? and who do i pick?