I sometimes do something essentially the same as your former friend because I think the person with the problem probably wants to be treated like a normal person to feel as normal as possible instead of as a charity pity case. And to take their mind off of their completely obvious problems of the moment. IE, "I know my leg is cut off, we don't need to go over it and over it ..." I figure everyone in the world is smothering them with that so I will not do that.
However, I know that is a gamble and had I judged that wrong, and someone said "Hello can it be about me today instead of about you? just today? My leg... is gone... I'm not over it." I would NOT be hanging up and never call again.
I might possibly if the way you said it didn't clue me in why you were saying it. If I felt you really didn't want to hear from me at a time like that, then I'd be gone. gone. I thought I would be there for someone when the chips were down and they apparently do not value that from me. What a dumbass I've been.
I started this comment with the intention to say essentially "If you were worried at all that you did something wrong, don't." because even if there had been that initial mis-reading of intentions, that doesn't explain disappearing, so it's squarely on them.
But right at the end there while actuallly writing this, I realized there is a responsibility for communication on everyone's part. I realized there is a plausible sequence of events where I had good intentions and you had good intentions and I had reasonable reactions and you had reasonable reactions and still we both came away thinking the other person is not great.
So now I no longer know if I have a point. Well these worthless thoughts were free at least. :)