No, I'm afraid someone's attractiveness doesn't take them out of the set of people whom it is immoral to emotionally abuse.
We are not obliged, in our personal interactions, to refrain from actions which cause other people any amount of harm whatsoever.
This being so, there must be a point where an action is bad if it causes a certain amount of harm, but okay if it causes slightly less harm.
That being so, "less harm because they are more attractive and can find partners more easily" can be one cause of the slightly less harm.
Previous thread: http://lesswrong.com/lw/mnq/instrumental_rationality_questions_thread/
This thread is for asking the rationalist community for practical advice. It's inspired by the stupid questions series, but with an explicit focus on instrumental rationality.
Questions ranging from easy ("this is probably trivial for half the people on this site") to hard ("maybe someone here has a good answer, but probably not") are welcome. However, please stick to problems that you actually face or anticipate facing soon, not hypotheticals.
As with the stupid questions thread, don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better, and please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
(See also the Boring Advice Repository)