When you always dance with the same partner, you learn to compensate for each other's mistakes. So there is a really good reason to dance with other partners (aside from the social aspect): it will improve your dancing. When you ask another lady to dance, have three dance figures in mind. If your new partner is struggling with the basic step, don't move beyond it. But otherwise, try one of the others. If she has trouble following, no big deal. The dance police are probably not there. And maybe you can see what she's having trouble with, and modify your lead. (But remember, you aren't there to teach.) Telling you not to panic, not to tighten up is likely to have the opposite effect. But if you mess something up, the sun will rise tomorrow.