what are the ANSWERS you wanted to hear, purple grape?
you described a young man who has cycled thru drugs, rehab, jobs and gf's quite rapidly. he's an IV drug user. he commited ARMED ROBBERY. that means he had a weapon and threatened someone's LIFE in order to get what HE wanted, i'm sure to pay for dope. have you ever had a gun held on you? or a knife? can you imagine the fear that is left with his VICTIMS that will probably never go away?
as it is, going to jail didn't straighten him out. he continued on the same path.
you say you've known him for 7 years but only as FRIENDS. that's the title of your relationship. but YOU have feelings towards him that exceed friendship. hon, if in SEVEN YEARS the guy has never asked you out on a formal date, or indicated he WANTS anything more out of you THAN friendship, then he just ain't that into you.
he's shut off contact before. it's what he does. if he WANTED to contact you, he would. he isn't. grilling his family isn't the way to his heart. surmising on what you THINK he might be thinking is an effort in futility.
it's interesting, in one statement you say he is your everything. and yet in another, you say when you go to school, if you don't MEET SOMEONE THERE, you'll have to go elsewhere. wanting to have a meaningful relationship is a worthy goal, but it really helps if first WE are strong and solid and then meet likeminded folk who are not active IV drug users and felons.
if you want to WAIT for this guy, spend MORE years of your life on hold hoping he'll come around, no one can stop you.