Hello and much love Ihatenotfeeling. You'll be okay! It will take some time but hang in there. I experienced a similar psychic devastation after 5 years of pretty heavy psychedelic/stimulant/opiate abuse, often in combination and including binges. I found myself in a state very similar to yours in which I enjoyed nothing, had no energy, no desire to get out of bed, and obsessive suicidal thoughts. Basically severe depression with a splash of inability to think clearly or express myself. I could hardly talk straight when trying to describe what I was experiencing or trying to tell stories, etc. I was feeling something like a literal road-block in my thought process, which manifested itself in a high pressure-like sensation in my forehead and top of my skull, causing the aforementioned inability to think clearly and express myself. i'm a fairly intelligent and thoughtful young man but I felt "blank", or grey, and my behavior and thought-process reflected this. I basically became mentally slow and very depressed, would cry for no good reason and felt despair and severe hopelessness.
Eventually I approached a physician when I reached a point that I was thinking about acting on my suicidal thoughts and how to go about it and, without saying too much to a doctor I was unfamiliar with, informed her that I was suffering from depression and crippling anxiety. I began the long process of finding an appropriate anti-depressant, eventually ending up on Cymbalta (which happens to block MDMA and MDMA-like drugs from interacting with receptors) after trying Lamictal, Wellbutrin and Effexor. I was using opiates (hydrocodone, oxy, dilaudid, kratom as the glue holding it all together) to cope with the numbness I was feeling and ultimately acquired a pretty severe dependence. Eventually, after falling deeper into depression I went through an opiate detox and rehabilitation. 2 and a half years of opiate addiction treatment, and abstinence from party drugs, later and I still have a tinge of the road-block sensation, but have regained my ability to enjoy myself and think/speak clearly. Things are much better now. I've been able to accomplish goals that I've had since before my days of partying and have found purpose in life.
My suggestion to you is to hang in there, continue searching for an anti-depressant that works for your mind and body. If a med doesn't jive with you after a month of taking it, it's time to try another. Sticking with a med that doesn't help you will get you nowhere. Absolutely cut out illicit drugs that interact with your serotonin and dopamine levels, I even had to cut cannabis out of my life (never thought I'd do this) because I found it only enhanced my emotional instability. I found an addiction counselor I could connect with to have another set of eyes on me and who I was able to comfortably bounce thoughts between. If this is relevant to you, I highly suggest doing this if you're able at all, but I don't know if you suffer from the disease or if you were just "having fun". Trust that things will get better and can begin to do so fairly quickly, though perhaps not at an amazing rate and not incredibly notably. Improvement will be subtle at first. You won't suddenly wake up one day feeling normal. I still experience the pressure in my brain that I mentioned, but it's not crippling as it was and it continues to diffuse to this day. I think I really started noticing improvement a little over a year later. Recognize that you've done some damage to your receptors and it will take time to heal. In the meantime, try to find a goal that you can begin to work towards. Keep your loved-one's/friends who understand the situation close and take it one day at a time. DO NOT TAKE ANY MORE PSYCHEDELICS/STIMULANTS.
People have done incredible damage to their brains and psyche and come back from it, you can too! I believe in you! Much love and I hope this helps a bit. -Snap.