Depression recovery. To some extent?

I'm taking antidepressants for 3 years. Have taken nexito, flutee,venla  and other classes of drugs like clona, amisulpridie, lithium. I'm not getting out of my depression completely. I'm doing regular work but my condition becomes worse when I try to indulge myself in any new activity as if my brain is resisting to new activity. It feels like I'm not myself anymore. When new meds are added I don't see any difference. Plz tell me that, is severe depression fully recoverable in everyone or u just get that much better that u can just function to some extent?My doc said it's something u have to mange with therapy. Only 50% recover,30% respond,20% don't respond. Sometimes I feel like killing myself coz my abilities have reduced after treatment. I'm 23, earlier I was topper in my class and I loved studying but now I hate it. I'm unable to take interest which was natural for me. Help me plz