hang in there,
you're still young,
and have a lot of time ahead of you..
stop trying to worry about not being a relationship and try experiencing life.. then maybe you will meet some girls..
also, as you get older, girls stop looking so much at looks and so i dont think your scoiosis is a problem becasue you seem like such a nice guy..
i think if you stop trying to dwell on your loneliness, and trying to enjoy life with no worries about what others think of you your depression will become more managable.. i know this is hard, but maybe try speaking to a counsellor abotu ways to go about this, or maybe if you need medication