I have a mix of diagnoses, including complex PTSD and SA and I used to have depression. It was almost impossible to figure out what needed to be fixed first since they all affect each other in some way, are related. But I found that if I'm depressed, I can't do anything else whatsoever anyway, so I had to work on that first. I literally forced myself to do something every day that made me feel better. In my case it was having some kind of connection with other people. So I started doing things online. I dreaded it, but then after, I would feel good. I kept doing it and after a while I liked it. I still have a long way to go tho. That was 3 yrs ago and i still haven't crossed over to involving myself with real life people. But, at least I'm not in front of the TV feeling completely useless and like a hopeless case anymore. I started making progress and then hope came back to me....it's going to take forever to get where I want to go, but now I know i will. The anxiety and traumatic past are things I still have to work on.
I don't know what the answer is. Maybe it's different for everyone. I know I was standing still for IDK how many years before I "got moving."
I don't believe in that serotonin stuff, at least not to the extent most people do I guess. I believe the environment has much more of an effect on people than biology. A depressive environment in the present or past experiences can cause chemical changes in the brain, but taking meds won't fix the environment....just like getting drunk doesn't really fix it either, lol! Alcohol and drugs both affect a person's brain, but only temporarily. The actual problems or life situations still have to be dealt with somehow.
What comes first the chicken or the egg I don't know.
Like is anxiety the result of low serotonin. Does anxiety lower serotonin. I don't get it.
Or is depression the result of low serotonin...or both anxiety and depression are. Like you said it is a lot to untangle. And that is why people give up and get drunk.
It's a bit more complicated, for example Benzodiazepines like Xanax help anxiety despite not touching serotonin. Most neurotransmitters have an effect on secondary systems further complicating matters, and as an example, Nardil, which is a very old medication from the MAOI class tends to be more effective for SA and depression than the SSRIs. Nardil is very broad spectrum in which neurotransmitters it affects. The SSRIs are of-course favoured by physicians, not on the basis of superior efficacy, but rather on basis of superior tolerability and less propensity to cause serious adverse events.
Unfortunately at this stage no one really knows exactly whats going on, so we're left with trial and error, if a certain medication class is shown to be effective in clinical trials and furthermore in post marketing observation for a disorder eg; SSRIs for OCD, then that's the benchmark medicinally until a further development or breakthrough occurs. There's always novel treatments in the pipeline but they take many years to develop and test thoroughly, which is why there can be a 5-10 year lag between new types of psych medications hitting the market.