I apologize in advance for a lengthy response. To cut to the chase, I chose “other”.
As a medical examiner I see a lot of suicides. With respect to motivating factors, at least insofar as those can be ascertained, in a very broad sense most cases fall into one of three categories: (1) People who seem to have a pervasive sense of hopelessness/emptiness/loneliness and simply do not feel like living, they have no specific reasons, they just can’t imagine anything will ever be different; (2) people who have identifiable problems and unwanted circumstances that they don’t feel can ever be solved, or that they can ever live with - a relationship ends, a job is lost, financial troubles, drug/alcohol problems, etc; and (3) people with a specific disease or generalized poor health, they are tired of living with the disability, limitations, pain, hassle, etc., and/or they don’t want to be a further burden on the people around them.
In another very broad sense, and allowing for exceptions, the above categories generally sort out into age groups, such that the younger someone is, the more they tend to fall into category (1), the older someone is, the more they tend to fall into category (3), and the more “middle age” someone is, the more they tend to fall into category (2). As I said though, these tendencies are far from absolute.
Why would a suicide be considered “selfish”? I can think of 2 general reasons. For one thing, it can be very hard, emotionally, on the survivors. There’s the grief of loss; often there is guilt; and sometimes there is a huge void in understanding - why did they do it? That seems to be the hardest thing in many cases, especially when the suicide is sudden and unexpected. A more tangible reason is that in many cases people leave behind some amount of loose ends and problems that the survivors are left to sort out. I suppose with regard to the first reason, someone could make compelling arguments why suicide is “selfish”, and someone else could make compelling arguments why suicide isn’t “selfish”. There doesn’t seem to be any obvious way to decide. With regard to the second reason, it’s hard not to think that it is selfish, and I suppose cowardly, to leave a lot of difficult and messy (both literally and otherwise) problems that others have to sort out, especially if the suicider caused those problems.
For me, being a sort of third party observer in the immediate aftermath, what seems more telling than trying to ascertain “selfish” or “cowardly” motivating factors is getting a sense of how considerate someone is of the survivors. You can get some sense of that from the notes, if there are any, which range in tone from apologetic and loving to matter-of-fact and bussiness-like to angry and accusatory. A much more tangible indicator is the method, time and place someone chooses to end their life. For example, when someone does something like shoot themselves with a shotgun in their living room next to the Christmas tree, with their children asleep upstairs (yes, it has happened), or jump infront of a random car on the freeway, it is very difficult to have pity for the suicider, and it is very easy to consider their act selfish in the extreme, regardless of what motivated them. Likewise, when someone obviously puts effort into minimizing at least the immediate impact and the practical hassle for the survivors, by, say, choosing a clean method, warning people before they enter the scene, clearing up their affairs and loose ends prior to the act, etc, it is more difficult to consider their suicide a wholly “selfish” act, regardless of why they did it.