He is too old. (not the age gap, which wouldn’t matter if you were both past 30 ) but at your age it is life experiences which make a 17 year old and a guy who is 25 in wildly different places. You realise you are vulnerable and I think you ought to take care of yourself here; if you find it hard to connect, then its totally natural to seize on a lovely, easy connection, which a guy of 25 (if he is 25, I bet he shrunk his age to seem less creepy, at your age I encountered a lot of that ) can easily fabricate.There are a lot of reasons a guy of 25 might be drawn to a shy 17 year old and honestly; none of them are great. You have so much time ahead with so many opportunities, and you are sussed enough to be using therapy to help with your issues, which is really impressive at your age, and I think that this is not the guy to help you move forward. Focus on all the great things you are doing for yourself, going to college, taking care of your mental health, and don’t put too much weight into a romantic relationship until you feel more comfortable with yourself, it’s part of life but you have a lot more than that to try to look forward to.