No child has ever said: "When I grow up I want to be grumpy!"
Therefore it is probably safe to assume that if someone is mean, grumpy or rough around the edges, there probably is a reason they are this way; most likely the person gone through a rough time to get there.
So instead of getting caught up on how we are being treating by a complicated person, how about flexing our compassion muscle and purposely putting ourselves in an understanding position? We can all understand difficulties and suffering, and having the intention to be caring is a small effort in exchange for a heartwarming moment.
Can you step a little bit more into compassion today? I'm eager to read about your experience in the comments!