I used to fantasize about doing this.

When it got to a point that I was making careful plans for how to effectively remove all traces of my existence before walking into the sea or something, I realized that it was probably not a good thing that I was fixating on this "fantasy" and how attractive it was becoming, so I went to a nice little family mental health clinic in walking distance.

I was diagnosed with depression, PTSD and general anxiety disorder. A few years and a few rounds of therapy and medication later and I'm... still struggling. But at least I'm not planning my exit. There's a lot to live for, but you can't see it when your brain starts running away with your mental narratives. Don't ruminate, don't fantasize. Get some help and do something new with your lives.