I don't know how much more I can take

I'm just tired of everything going wrong. Feeling inadequate in every way possible and trying so hard to move up and be better only get knocked right back down. Trying for decades hoping it will get better only to find myself getting worse. I don't even remember what being content feels like anymore. What's worse is i've tried numerous times to kill myself but was too much of a coward to go through with it. Now I'm just angry that I can't even do that for myself. I need to put and end to this tonight. It needs to stop.