> If you think that SSRIs don't affect serotonin

I didn't say that, I said that "increasing serotonin" is not why these drugs sometimes help people feel better.

> Honestly, her coke habit is the lede here,

Yes. In the long term, cocaine use wrecks the mitochondia, which contributes to exhaustion. The proper therapy in this case is to restore the mitochondria density. Etiology (" a branch of medical science concerned with the causes and origins of diseases") is thrown out the window when a patient is prescribed an SSRI.

> not the scare story that might turn other people off to treatments that work for them.

The BBC story that this submission links is about how SSRI treatments sometimes wreck people's lives. You should read it. My comment was that adverse effects of these defective drugs (SSRIs) have been known from the very beginning, and I said a few words about alternatives that work better.

> In the long term, cocaine use wrecks the mitochondia, which contributes to exhaustion. The proper therapy in this case is to restore the mitochondria density.

In mice, when given super high doses. The data for humans is much shakier and the effects of this are unknown, or if there are any, or if it even matters. AFAIK, none of the long term studies from reputable sources have shown long term effects on wakefulness or motivation past the initial withdrawal syndrome. This is just some new "meth neurotoxicity" hysteria bullshit to scare people into thinking drugs are bad.

Going on my observations, cocaine is a much safer drug than meth amphetamine. She recovers quickly from cocaine, but it takes 3-4 days for her to recover from meth amphetamine use.

That doesn't have much to do with safety, more with half-life. Methamphetamine has a longer half-life (averages about 15 hours) than cocaine (about 5 minutes to an hour depending on route of administration). With long term regular use they both have problems. Methamphetamine can be neurotoxic in higher doses without the protection of tolerance and might cause Parkinson's disease later in life. Cocaine has circulatory effects long term, and if smoked causes damage to the lungs. With short term or occasional use they really aren't that bad for you in general (as is true with almost all drugs).

> I didn't say that, I said that "increasing serotonin" is not why these drugs sometimes help people feel better.

Yes it is. Only some people don't have too little serotonine.

Then, can the lack of serotonin really be the main, or only cause of depression ? If people with sufficient serotonin levels can get depression, then how can we argue that the actual increased seratonin levels is what helps people recover from it ? It seems like a quite strange argument to me.

Because depression, like most psychological diagnoses, is defined as a pile of symptoms, not as a specific illness like the flu. We don't know all the different things that can cause depression.

One of the things that we're reasonably sure can cause depression is decreased levels of serotonin. That doesn't mean there's not other things which cause more-or-less the same set of symptoms.

EDIT: On a note related to your girlfriend... people can appear externally happy while being seriously depressed. From talking to me irl, you'd likely never guess that I self-harm, have no motivation to do anything, and wish I were dead. You can't blame someone for wanting an escape from that.

Do you have a citation for your claims? Specifically that low serotonin levels CAUSE depression in humans?