You might want to look into "The Lifestyle Cure" which has a fairly high cure rate for depression using a combination of omega-3s, sunlight & vitamin D, exercise, social interactions, mental habits to avoid negative ruminations, and improved sleep:
https://tlc.ku.edu/From the author: "We were never designed for the sedentary, indoor, sleep-deprived, socially-isolated, fast-food-laden, frenetic pace of modern life. (Stephen Ilardi, PhD)"
Dr. Ilardi has written a self-help book based on the elements of TLC, "The Depression Cure: The 6-Step Program to Beat Depression without Drugs".
The book has an example of a guy who suffered depression for about forty years and within a few weeks moved beyond depression following this approach (much to his own surprise).
In another comment to this topic I mention this book and various other resources: https://www.goodreads.com/book/show/134266.Out_of_the_Nightm...
""Out of the Nightmare" presents a no-fault theory about depression and suicide. It argues that we should not blame the victim, the family, the caregivers, or society in general. It provides a detailed analysis of each of the barriers that stand between suicidal pain and recovery, and provides those who suffer from depression with hundreds of resources to find their way out of the nightmare. Recovery from depression is decomposed into recovery from envy, shame, self-pity, grandiosity, fear, stigma, prejudice, and the vicious circles of suicidal pain. The book helps sufferers find lasting relief from internalized negative self-judgments."
The key point there is to see suicide as an involuntary action that happens when pain exceeds coping resources. It is often possible to reduce pain (whether physical, emotional, or social). It is also often possible to increase coping resources of various sorts -- and different ones work for different people.
You mention a sense of obligation to your loved ones which is a coping resources of a sort. So is momentum of routine habits, which in a way are another coping resource. So, perhaps you might be able to build out from those -- perhaps to help others more directly and to develop new lifestyle habits to improve mood (like in the TLC approach)?
The book also suggests taking the time (ideally within therapy or consultation with some caring person) to outline all the hundreds of painful things that contribute to your depression (even events from the distant past) and then working towards improving the most approachable pains that are easiest to fix (e.g. an uncomfortable chair, a toothache, a specific negative self-judgement, a strained relationship, etc.) to make some positive progress. All easier said than done of course to get started, but a little positive progress may then lead to an upward spiral of other positive progress and so on. While it may be impossible to improve every painful situation in your life, if you can at least reduce several pains in your life, that reduces the impulse towards suicide.
Another book is aptly named "The Upward Spiral: Using Neuroscience to Reverse the Course of Depression" covers some of the same ground:
https://psychcentral.com/lib/the-upward-spiral-using-neurosc...
"After he describes the downward spiral, Korb helps us start moving in the other direction. He encourages readers to take small steps, since any change, no matter how tiny it seems, can have big effects. Making small, even somewhat trivial decisions when we are indecisive can help us feel productive, he writes, and is one step in the process of reversing depression. In addition to setting goals and making decisions, Korb advocates getting adequate rest, exercising, and developing positive habits. Most of his advice seems straightforward, but what surprised me was his emphasis on gratitude. Research suggests that opening a so-called gratitude circuit can have great positive effects on our brain. It not only decreases symptoms of depression, but also improves physical health, improves sleep, and boosts serotonin. Gratitude also plays a role in the production of dopamine, Korb explains, the neurotransmitter that increases enjoyment. And so, by activating our gratitude circuit, it’s easier for us to feel positive emotions."
And here is a more radical idea (YMMV, so just for leading-edge background, not necessarily recommending):
https://michaelpollan.com/books/how-to-change-your-mind/
"So began what grew into a two-year journey into the world of psychedelics—LSD, psilocybin, Ayahuasca and 5-MeO-DMT. The book explores the renaissance of scientific research into these compounds and their potential to relieve several kinds of mental suffering, including depression, anxiety, and addiction. It also delves into the rich history of psychedelics in America, tracing the promise of the early research in the fifties and how a moral panic about LSD in the mid-sixties led to decades of suppression, just now ending. I spend time with neuroscientists who are using psychedelics in conjunction with modern brain imaging technologies to probe the mysteries of consciousness and the self. Several of the scientists I profile are convinced psychedelics could revolutionize mental healthcare and our understanding of the mind."
Also, for any typical HN poster (maybe not you), looking into whether Asperger's syndrome affects your life and relationships may also be enlightening as Asperger's is associated with lifelong anxiety and depression from social anxiety as well as about a 10X higher than typical rate of suicidal ideation...
https://psychcentral.com/news/2014/10/13/suicidal-thoughts-1...
I list more coping resource here including about Asperger's on the job among many other job-related issues: https://github.com/pdfernhout/High-Performance-Organizations...
All the best in finding ways to reduce your pain and increase your coping resources that work for you in your specific situation.