It sounds to me, from your symptoms and your writing, that you could be experiencing a depressive episode. This could be caused by various factors including your use of AAS. I'm by no means a doctor but I have studied depression extensively both in my academic career and personally.
Welbutrin is a great drug with very few sides. One of the sides, however, is often an increase in libido and performance. As a matter of fact, it's often perscribed concurrently along with an SSRI (e.g., Zoloft or Paxil) to combat the sexual sides which often accompany that class of drugs. I emphasize Welbutrin is not an SSRI. If I were you I would see a psychiatrist immediately and get an evaluation. Fuck the stigma and give a shit about yourself. A psychiatrist is not going to tell LEO that you're a juicer but s/he will, however, treat your depression.
I've dealt with depression and overcame it -- it took me literally over a year to face it and that was a wasted chunk of my youth.
Good luck.