Dude you sound like me. This is how I have felt all my life and even when I first entered university. I entered a very good university and all my life had given emphasis on school and studies and nothing else. Even when I entered university I also felt jealous of people and the friendships that people had with other people etc etc. Even monetary wise I felt jealous even though there was no reason to do that. There was a point when I also contemplated suicide and I was so close to the edge. Then my mum was the one who brought me back to being normal. She told me I was having having thoughts which are bad for me and which are leading me to a path of self destruction. It took years, but by now I am a completely different person. I am famous, I have friends and those friends who are genuine, I am still doing better than ever in university and I am happy.
How I came out of this phase and thoughts of loneliness? I thought it is normal to feel this way because I am a new student in university and I am like a little fish in a big pond. I will have to personally do something for people to notice me. No one is going to come to me, I am going to have to go to people as this is not school any more. I am supposed to act like a mature individual because I am in university now. Yes I was at a disadvantage because before in school I did not socialise much and I was always concentrating in studies and playing video games. Yes I did play video games and yes I was BEATEN too when I was growing up so I can fully understand where you are coming from.** I am still beaten but heck, that is a different issue. **
You have to stop with these thoughts of self pity, and be strong. You have to join university clubs, and start doing work which people will notice. Once people notice your work, they will notice you. This is how you socialise and be known in university. Through your work and how good a human being you are not from your financial background or what your family name is. Smile, be happy, you are only 18(trust me I was 18 too when I joined university, I totally understand how you are feeling), and do what I told you too and iA have faith in Allah and everything will be all right.
That does explain quite a bit. Sads. :-/