I get where you're coming from. I lost my Dad in December of 2016 and my Mom in March of 2018. I was close to both but especially close to my Mom, and it's been difficult to get over the pain of her being gone. I also suffer from clinical depression and anxiety and have been treated for both. I've also had 2 major heart surgeries, and the 2nd one really seemed to exasperate my depression for some reason, even though the surgery was successful and I'm reasonably healthy with only minor physical limitations due to its success.
That surgery was in 2011 when I was still drinking, and by 2013 I was contemplating suicide regularly. I was in that spot I mention frequently where I couldn't imagine living with or without alcohol any longer. While I still miss my Mom terribly...and while I still struggle with bouts of depression and anxiety...I firmly believe that if I pick up a drink today I wouldn't survive very long...maybe a year, probably less.
There are several things that get me though the down times today. One is knowing that it is temporary as long as I don't pick up a drink. Another is remembering how bad it was when I was near the end of my drinking. When I'm in a funk and think back to the end days of my drinking I'm like "oh yeah, today isn't that bad after all". Moderate exercise also helps. My main source of that is walking (have a "greenway" with paved walking/biking trail right behind my house). I really slacked off on this over the hot summer and I have paid for it mentally. I just started back daily walks and I can already feel the difference. Finally, helping others always helps even if nothing else seems to. It gets my mind off of myself and my problems like no therapy or meds has ever been able to do.
Finally I'm a big fan of Jordan Peterson's take on life and personal responsibility. Just watching a coupe of his "pep talk" videos on YouTube telling me to "clean my room" and "life is suffering so get my act together" seems to help me put things into perspective. Here's a couple videos if you (or anyone else here) are interested in watching.
This one is a classic rant
This one is a compilation of his "nuggets" of reality: https://www.youtube.com/watch?v=XICqcAac9jg