If your partner is having problems at work, whether it be being ostracised by work colleagues or maltreated by their manager, or having problems with friends outside of work, do not step in. It’s likely that given the problems, when you show up doing your Clint Eastwood act, their colleagues/friends/manager will not be willing to concede that despite their dislike of your other half, you are indeed good looking. Their animosity for your partner is likely to be such that they will try to find fault with you as well. They will pick on a minor physical flaw and attack it.
Don’t put yourself in the firing line. Don’t offer to intercede. Your partner’s enemies will not be in the right frame of mind to laud your beauty. To them, you are ugly even before you show your face. Step back. Let your partner resolve these issues. Try to avoid asking your partner whether these issues have been resolved.
Months later, when the dust has settled, perhaps a social occasion will arise where your partner will ask you along and these former enemies of hers will be more inclined to accept that yes, you are indeed very easy on the eye.