Severe Insomnia: How do people make it with so little sleep?

My wife's psychiatrist diagnosed her over 40 years ago, with schizoaffective disease, takes an anti-psychotic med daily, that totally controls episodes... however, it seems to have given her insomnia and sever depression. Over the years she has tried numerous meds, some that worked, and then some that didn't. As she went without quality sleep, her depression worsened. About 20 years ago, she would take Deseryl/Trasodone with a Dalmane... worked well for about 10 years, and she was happy. Then either both meds stopped working for her, and or the generics weren't as good as the brand, she was then switched to just Temazapam/Restoril for sleep and depression... with Xanax .25mg, on an as needed, no more than 3/day, basis. Again, worked in the beginning, 10 years ago... but kept needing more and now, she understands that the side effects, for her it's nausea with dry heaves, come from taking to much Temazapam, 60mg, or from having too little in her system. I am trying, with her dr,, to gradually get her back to only taking 30mg. She wants to try TMS for the depression, hoping that a major mood change, may give her life meaning and purpose, along with restorative sleep, but will not start the TMS until the nausea and dry heaves are gone. This has been her experiences, just wanted to share her path.