I think you are obsessing over trivia here.  HER2+ doesn't mean that
hormone therapy doesn't work, it just means that the probability of
recurrence is a bit higher.  And there is not as yet conclusive evidence
that there is anything that can be done about it.  Unless we can find a
reliable way of determining which patients would relapse without
Herceptin, it's not really likely that giving it to every early stage
patient who tests HER2+ is going to be sensible.

Here in the UK as far as I know they don't even test most early-stage
patients for HER2, there is no point because the result isn't going to
change the prescription.

I can understand if they are equivocal about chemo if she has emphysema,
for two reasons.  One is that her ability to cope with the side effects
is reduced.  The other is that her life expectancy is rather shorter
than a healthy person, so the potential gain in (quality) life
expectancy from chemo is reduced.

I suspect that they weren't taking her uninformed opinion about chemo as
an overriding decision, but were checking whether she had any strong
feelings about it.

I would also point out that any heart condition that is a problem for
A/C would probably also contra-indicate Herceptin.

Hormone therapy is generally reckoned to halve the risk of recurrence,
and it is pretty safe.  Hence the doctors' faith in it.  Not that it is
guaranteed to keep her alive (no-one can do that while she still has to
cross the road occasionally), or even guaranteed to prevent another
cancer,  but that it may well be her best bet for living as long as she
can. There simply -are- no guarantees.