Many people have recommended that show to me, but I have not yet watched it.
I have written before about how hard and hurtful it is that our spouses have chosen an elective death. I think the reason I have never been able to end a relationship (even when they were unhealthy, not bound by formality and no kids were involved) was because I did not want to have to grieve. That is a really hard experience and choosing it was something I could never do. Like you, it does not make sense that others can do it. Or elect to do it. Do they value another person less? Or themselves more? Perhaps they are stronger for it. I do not know. Its just a different perspective that I do not comprehend. its cold and self serving. But maybe it would have been better for me to have been more self serving. My life would have been better. Maybe its a better trait to have for evolutionary purposes.
Regarding addiction, it is annoying when movies and books neatly tie it into that "this is us" package you described. My ex was way too high functioning to be an addict. I didnt know you could be a junkie and not be skinny and on the streets. And instead of seeking help from me or AA meetings, he just kept his secret hidden by divorcing me. But not until after he villified me and marriage. Maybe I wont watch that show now!
I like your garbage truck analogy. I think its just a matter of perspective though. There are some people that prefer and find more security in something real and tangible. There are others that prefer ease and good feelings even if they are fleeting or not real. It works when 2 people have similar perspectives maybe.
For me, marriage was symbolic of family. Meaning, sure we all have flaws but family is family and you take care of each other because of love commitment and tradition. I never expected it to be endorphin filled or disposable or life coach quality.