Commuting, I'll cuss about winds over 15 mph but I'll ride unless the gusts are over 45 mph. Although I will change my route to avoid all those lovely, big, old trees which might decide to do some self-pruning as I ride underneath them.
Fun rides, I'll check the wind forecast carefully before heading out if it's blowing over 20 mph. Take my medicine outbound, then let the wind blow me home. It's easy to say, "Take it easy going out with a tailwind," but it's much harder for me in practice.