I didn't read all of the replies in detail so if I'm repeating information my bad. This is the other half of the Riso/Hudson recommendations from the book Understanding the Enneagram: The Practical Guide to Personality Types -
6. Talk open with someone you trust. This need not be a therapist, although it might be. You need both to express your feelings spontaneously and to have someone react honestly. You may well discover that you are not as different or as much of an outsider as you sometimes feel you are. Paradoxically, one of the surest ways of "finding yourself" is by being in a relationship with someone else.
7. Community service of some kind will make you less self-conscious and give you a better perspective on yourself. There are good things in you that you have kept hidden, possibly even from yourself. Find out what they are by getting involved in practical service.
8. Do not succumb to self-pity or to complaining about your parents, thoughts of you unhappy childhood, your unfulfilled past, your failed relationships, and how no one understands you. Someone would likely understand you if you made a real effort to communicate. (One of your unhealthy claims is that you have been damaged by your upbringing and are therefore exempt from having realistic expectations of any sort placed on you). Use your self-knowledge to be aware of the true effects of your negative attitudes.
9. Do not take everything so personally, thinking that every remark is aimed at you. And even if one occasionally is, do not go over it in your mind. After all, a critical or hostile remark does not reflect the whole truth about you. Usually, people are too busy worrying about themselves to scrutinize your thoughts or behavior in such detail. If in doubt, get reality checks from others -- ask them what they meant.
10. Beware of the harshness of your own self-talk. You tend to say and do things to yourself that you would never dream of saying or doing to anyone else. Learn to notice the inner voices of contempt and self-rejection that you entertain. Cliche though it is, become a friend to yourself. Stand up for yourself and give yourself a chance.
I checked out the Enneagram Riso books from my university's libraries and ironically the only dog eared pages are regarding Type 4s. Go figure. Personally I really like the community service idea listed because it allows you to get outside yourself while feeling good about doing something for someone else. It also creates opportunities to build meaningful relationships in the sense of finding others to relate to. Seeing that you're a university student as well, are there any types of community outreach programs or community service projects that are creative in nature near you?
Both of the books have sections where they seem to tell 4s to get out and experience the world rather than living in their heads and I feel this has been true for myself as well. I feel most normal when I'm engaging with others or at least experiencing sensory activities that can ground me. You mentioned that it's hard to find your way back once you've lost the connection (I can totally relate) but perhaps finding some sort of regular activity you can take part in that has some sort of creative meaning interacting with others might be a place to start? I'm not sure what kind of opportunities you have in your area of the world though.