Please tell me, could the effects of bullying be reversed/fixed?

It depends on the: effects as far as reversing them. If your suffering from a history of bullying, see a psychiatrist for evaluation for possible medications if warranted (i.e.: depression, anxiety), and a therapist to work on ways to cope with how you've been affected by the bad behavior of others. The most important thing is, is the bullying in the past, or is it ongoing?

Eval: Get a full psychiatric evaluation to determine what bothers you, and consider medication to take the edge off them symptoms. Next, get a referral to a reputable psychotherapist to discuss what your current emotional state and life experiences men to YOU, including what it was like to be bullied. Meds and therapy together are the most optimal approach, for the most part.