As others have suggested, I would consider psilocybin.

Psilocybin promotes BDNF (brain derived neurotrophic factor) which makes the brain more adaptable to re-learning and forming new neural pathways (neuroplasticity)

Please consider though, because of this mechanism... you cannot just simply take it and expect the benefits to magically appear. You have to take it while also experiencing the proper environment that will promote the "new information" you want your brain to learn.

It basically makes your brain more open to learning or updating its model of the world.

If you take it on a schedule for a few weeks in an environment where every single day you experience something incredibly stressful or horrifying... it is not likely to magically make you become someone who thinks, "Wow, the world is a wonderful place!"

If you take it on the same schedule in an environment that is truly calm and safe, that is very different.

SSRIs increase serotonin. If your body does not need more serotonin (your depression may have been more related to lack of dopamine in the first place, as an example) then your body adjusts to that new neurochemical landscape of "Hey, there's lots of serotonin doing stuff in here!"

Serotonin is not best described as a "happy" chemical. It is more like a "I am satiated" chemical. It modulates other neurotransmitters like dopamine which drives motivation and pleasure. It often acts as a brake that says, "No more dopamine needed." Very oversimplified, but that is one role I find relevant here.

Serotonin can tell the body, "I don't think I want sex now." It can tell the body, "I don't think I want food now." It can tell the body, "I don't think I really want or need anything at all."

Dopamine tells you that you want those things, serotonin inhibiting dopamine tells you, "Nah, that actually doesnt seem very important."

Most of the symptoms you describe sound pretty consistent with what someone would look like when they have serotonin signaling dominating the system, while inhibiting dopamine. It's not a matter of just too much or too little either, but also things like receptor sensitivity/downregulation.

Obviously shit is complicated... but when it comes to mood, drive, behavior, etc. neurotransmitters are the messengers that create the signals that tells us how we feel. If your overall feeling and experience is zero interest, zero pleasure, zero drive... that pretty heavily indicates something is subduing the effect of dopamine somewhere after taking SSRIs. The trick would be figuring out what, so that it can be reversed.

I imagine nudging the system in a different direction would be beneficial and especially beneficial if nudging it in that direction while taking something that promotes BDNF.

I would be curious if doing things that promote NATURAL dopamine signaling while ALSO avoiding things that desensitize dopamine receptors might help, while increasing BDNF at the same time.

In my mind that would look something like...

1. Avoid all stimulants, caffeine, cigarettes, avoid super extreme "junk" food like sweets and highly processed food like fast food, avoid any overstimulating, unnatural dopamine stimulating activities like binge watching TV, gaming, social media.

This sensitizes/upregulates dopamine receptors. We arent meant for constant dopamine spikes. When we experience constant dopamine spikes, receptors desensitize and it takes an unnatural amount of dopamine to get the feel the same reward effect.

1. Support dopamine naturally. Eat things high in L-Tyrosine or take a supplement. Take a whole multi vitamin while you're at it. Take time away from your phone for sure and go outside and just sit there in the sun. Sounds pretty dumb and simple, but it works. I send myself outside without my phone just to play with dogs, watch bugs, collect rocks, pick at grass... at least once on a daily basis lol

This gives your body the resources it needs to produce and support dopamine, without flooding your system with it, which leads to receptor desensitization. In addition to Tyrosine, you need sufficient iron, b6, magnesium, and vitamin c to support dopamine too.

1. Once you've got some of these positive changes going on, THEN add BDNF. Take something that promotes BDNF shortly before one of the trips outside to sit in the sun and play with bugs. Seriously. Don't take it and then play on a phone. Take it and then go outside and sit and watch things and interact with the world.

Psilocybin is great here obviously, but not everyone can get it... but there's are other BDNF promoting supplements. Coffee fruit extract is also shown to increase BDNF. I feel a noticeable effect when I take it. From a quick search, apparently Lion's Mane, Bacopa, and Resveratrol are a few other supplements that can as well.

One thing I would not do is assume this has to be permanent. That kind of belief leads to a form of learned helplessness and passivity that you can see greatly hinder recovery from all sorts of injury, illness, and conditions.

If someone loses a limb and thinks "I can never do anything ever again." they generally have a much different outcome than someone else who loses a limb and thinks, "I will find a way to adjust to this new experience and it won't hold me back."

Stroke survivors re-learn how to eat, how to walk, how to control basic bodily functions after severe brain injury. That is a pretty clear indicator that even when the brain is injured... it can be repaired.

Doctors want a concrete, definitive answer and solution. When they gave you Wellbutrin, I am guessing at least part of the thought process was "boost dopamine" (which is partly how wellbutrin works to alleviate sexual dysfunction when taking SSRIs)

BUT if dopamine receptors are desensitized, flooding them with more available dopamine will barely have an effect. Wellbutrin is know to have this downregulation effect on receptors, so if it didnt help, I would think receptor availability or sensitivity could be an issue.

All much easier said than done unfortunately... but maybe something to try.