Source: Years of depression, complex trauma work and effects, and suicidality + making a turn around the bend several years in.
To speak to your drug question, SSRIs are first line treatments that have a lower success rate but are moderately successful. I recommend talking to a doctor and starting on _an_ antidepressant earlier rather than later. This way if you're antidepressant resistant you can go for a treatment modality that's exceptionally effective -- Ketamine infusions. Expensive but if you're able to extend at home supervised with troches/nasal and follow the rules you should be fine. ~70% for IV Ketamine and ~60% for esketamine nasal treatment, in terms of success rates.
There are many atypical antidepressants that are hard hitting. You can get creative with the dopamine system. Fisher Wallace and other brain stim devices are out there. Barring all that, deep brain implants and ECS (ecs is not too terrible I've heard compared to what it seems) are options. If much fails you might be able to access psychedelics through right-to-try laws or in a locally legal state.
You'll need therapy as well. It will probably take you 4-5+ therapists to find one you click with. If you plateau for a few months then move on to a new therapist, but try to find one with a goal of staying for a few years.
I say this as the person who would be near the tip of the most resistant category. We have Dissociative Identity Disorder (officially diagnosed), which is one step beyond complex PTSD, as well as both subclinical NPD and diagnosed Borderline Personality Disorder. BPD sucks like nothing else.
Obviously these make a huge impact in our day to day life but we've been able to crawl out of the hole and are well on our way to rebuilding friendships, relationships, and a relatively content life, just with a good foundation this time. I still have a few years left but am so much different. Ketamine helped me so much, as well as personal value reshaping.
If it helps -- the similarity between morbid depression and the most enlightened person on earth is the knowledge that nothing truly matters and that there is no meaning in anything. The difference is that the enlightened person has let go of putting value in finding the meaning of anything.
Integrating the above paragraph has probably done the most overall in relieving the pain and symptoms of my cluster B disorders.
If you want a good workbook I know several, Janina Fisher's "Healing the Fragmented Selves of Trauma Survivors" is generally excellent.
One hard thing is for people like you and me who have been in pain for a long time, our brain does this beautiful thing to try to reconcile it by finding meaning in pain. Unfortunately that shapes our identity and makes a fixed global attractor around pain -- i.e. we can run from it, but our identity always wins out against our actions. The endless hill always wins out against the man pushing the stone.
You can do all the work you want to heal but if you do not let go of finding meaning or value in pain, or being hurt, or whatever collection of meaning-making beliefs you have, the hill will be there and thwart your efforts.
Even positive feelings like "love" as a core value can cause pain, this is because the world contradicts and clashes with it. Dysphoria is not just for gender issues, it is for all identities. And dysphoria is stronger than pain aversion, hence why some people like you and I seem "permanently broken". But it's all an illusion.
If you've had a spiritual awakening moment at any point, "The End of Suffering" by Adyashanti is really, really good. If you haven't feel free to read but it may feel like hippie dippie nonsense.
If you're looking for something to find a compass of where you should move emotionally when you're stuck, whenever you're despairing if you commit to reminding yourself that you're no longer a person who needs meaning to live, something will move or hurt. Keep repeating that to yourself whenever you get stuck and it'll give you a good GPS direction on where to go next.
But if you're super deep in the depressive slump, just survive. Your mind is your worst enemy right now, it will lie to you and limit your options. Just keep going. Even if in the worst case the above is a bad roadmap (I certainly don't believe it is a bad roadmap), at least it's a roadmap. I'm six, almost seven, years into what feels like a near full time journey trying to survive what has felt like hell on earth, and I'm well past the worst point. The reason I'm so detailed is probably because when I was alone and crying out to God for help that I wish someone reached out to me. So I think it's to amend for my own past hurts on that front.
Much love and we're happy to answer any questions.
T,S&company.