When I think of situations like I described two responses come to mind:
1) Not getting involved - which does not help the person and at worst may leave them feeling abandoned
2) Getting involved - where people are often reading their own story into someone else's and doing more harm than good
It seems your advice is 1) and the "want them to want me" is 2)
Certainly the Buddha got involved in other people's suffering, so 1) does not apply to everyone all the time
From the little I've heard I get the impression the teachings suggest "doing no harm" as the priority. A gross simplification might be sort your own shit out first then worry about others. But for a layperson that would mean not intervening in this lifetime.
Consider the case you mentioned, if the person is physically helpless you decide it is OK to feed them. We could liken this to raising a child - parents get involved and create conditions that they hope will be beneficial to the child's growth (both physical and mental).
We draw an artificial line in the sand when someone becomes an "adult". Then they should ask for help and that works well for well adjusted people most of the time. But I don't think we stop growing mentally and I've often appreciated help when it has been offered. Some of the most insightful help came from being challenged in assumptions which by definition I was not asking to have changed!
I guess what I'm saying is that many adults are not equipped to deal with the situation in front of them. I suspect that most people follow 1) not because of a great wisdom but because they are afraid of getting hurt themselves - as you mentioned it gets dangerous if you fall into 2). Many people have been "burned" by offering what they felt was kind "help".
Maybe the teachings don't have much to say about these types of social questions ?
I was introduced to Gestalt listening not that long ago. It is the idea of not advising but sharing relevant personal experiences. I don't see this as ideal because one can easily read one's own story and not grasp the other persons perspective but it gets away from offering advice.
If I was going to try option 3) I think it would need to be founded on not giving advice. But rather than sharing my experience it might be wiser to try and fully grasp the perspective of the other, then I can be an effective mirror for the other to see their own situation. I suspect that we often just need to "get some distance" from our own situation to see solutions or ask for advice. It is a bit like meditation in fact!
Interested to hear more of your thoughts, thanks.