It's really not too terribly difficult to deal with a few years of college if you have the right mindset. Young people who generally keep to themselves and are extremely focused will probably be better off than most. Even state schools are not that bad, ours at least.
-Commute or rent an apartment by yourself or with a studious and trusted friend or fellow student. They do exist. You want the type that stays in the library basement half the time. Staying in the dorms is not a good idea, Catholic or not.
-Go to campus for classes, review sessions, exams, work if applicable, and studying when necessary. Find quiet areas to study when in between classes, etc. Try math libraries, other libraries, and other study areas and atriums within the buildings. Otherwise, study at home (wherever that happens to be).
-I can't recommend many degrees where you'd be well-off as a Catholic earning, and most of them are useless anyway, if you actually plan to find work later within that field. Try science (physics, biology, biochemistry, whatever), engineering, maths, agriculture, and other hard sciences. Stay away from literature and other soft majors.
-Be polite with fellow students but stay away from those that rub you the wrong way. It really is not hard to avoid bad company. It's not hard to avoid being "too friendly" with the opposite sex. In fact, you will, if you follow the advice above, you won't even have to avoid it because you won't be around it hardly at all. (You still might be around people of the opposite sex but it's not going to kill you.)
-Stay occupied. Work. Work in a lab or anywhere else morally neutral. Which happens to be most jobs, in all likelihood. Have hobbies and occupy yourself with them. Take up knitting, metalsmithing, birdwatching, polo, or whatever else floats your boat. Study and commit yourself to doing well.
-Assist at Mass as often as possible and pray the Rosary every day.
This worked for me, and I have no doubt that it will work for others. Maybe not everyone, but surely someone.