The intended topic (albeit not communicated very clearly by use of examples from my husband's work) is being generous vs. being a pushover. The specific incident wasn't supposed to be the whole topic. But that's me not being clear.
I see, thanks for clarifying!
Personally, I have difficulties operating with the category "pushover". It seems to make the thought process unnecessarily complicated.
I guess if I were to ask the question, I would word it something like "When can I refuse a request?", and my answer would be: "That´s always an option." It´s a request, and a request can be answered yes or no.
If a person reacts to a "no" with appeals to morality, they reveal that their request wasn´t meant as a request, but as a demand or claim.
In my understanding, however, demands and claims have no place in human interaction.
Maybe you are looking for objective criteria when to respond to a request "yes" or "no"? I can´t help with that question - because I don´t know there are such objective criteria (and, on second thought, I am not even sure I could come up with a consistent set of my subjective criteria).
Like, upon the request of a social worker, this weekend I did a rockband-coaching in a jail. For free. I think it was a great experience for everyone involved, I had a good time and some inspiring encouters with the guys.
In the end, one of the prisoners said: "Can´t you come here to teach us on a regular basis?".
I felt that committing myself in this way would limit my other weekend activities (which either contribute something to make ends meet, or are needed for recreation) too much, but doing this voluntary work on a case to case basis would be ok. This is how I feel about it, this is what I said to him, and this is how I´ll go about it - but I don´t seem to need an objective-subjective consistent set of criteria to justify this decision.