I don’t think Mumkey will neck himself any time soon. There’s a couple reasons for this.
First, he’s getting a job. That shows he’s thinking of the future somewhat. So that could push his final act back a bit.
Second, he still has people he cares about, or at least his cat. People who care about you don’t matter if you want to die, but the other way around does more. You don’t want them to suffer because you care about them.
Third, and this one is really weird and may be bullshit, he has thought about this for a long time. In my experience, you just get used to wanting to die, and it doesn’t hit as hard anymore to the point you can ignore it. This may just be complete bullshit.
Fourth, he may have something he’s waiting for. He’s mentioned before he’s thought, “I’ll kill my self after Breaking Bad ends,” and later, “I’ll kill myself when Infinity Wars comes out.” He had something he wanted to see or do that kept him holding on, and I think he may again. Don’t know what though.
The only thing I think would drive him to do a flip is his mindset brought on by the pills. They clearly aren’t good for him but stopping abruptly would be even worse.
This may just be me hoping though.