You know, i wish i could cry, it's a way of releasing all your emotions that are bottled up, but i can't anymore, and because of it i feel like some kind of empty shell. Theres no harm in crying, but it obviously indicates you aren't feeling well.
Don't worry too much if you don't get voted in as a rep. I tried running for treasurer last year for one of our societies (so kinda similar in some respects), and though i was there much longer than the other person running for the position, knew a lot of the people in the society and had helped out the society with a bunch of things, i lost. I think partly because i was up against a girl.
Sadly, when it comes to being voted for something its mostly a popularity contest, so the extroverts tend to win. If you do get voted in gratz, but if you dont, you won't have the stress that comes with it
Its funny that being a genuinely good student/pupil brings so much hatred from peers, even at higher education. People will always see the bad before they see the good in someone, and assume the worst rather than the best...and then there's jealously. Theres lots explanations for why people may look down on you, but none of them are valid. Stand tall, keep being awesome, and eventually you'll see that people are using your standards as a goal to aim for, which is something to be proud of. That said, take that with humility when it happens.
The sleeping with the friend thing is kind of natural, to seek comfort in someone you know. Personally, i think the fact you have someone you can have sex with whenever should give you some confidence in your looks and personality, but i'm biased since i havent been with someone for over 3 years.
You'll get over him eventually, i know that sounds cliche but its true, from personal experiance. It's just the time it takes can last a while and be painful.
I would mention this depression to a GP if you haven't already, depression and anxiety problems are a common thing they deal with, and they deal with it all professionally, they can give you more options. As for your counsellor, mention as much as you can; the more you tell them the more they can help. Its like with anything, the more information you are given the more you can work out to fix things.
As for the friends thing, theres always us peeps on here ready to chat