I'm going to choose not to attend a rafting trip with coworkers because I don't want to bring my spouse along
Why do you not want to bring your spouse to your rafting trip?
I want to go to various places without her.
It's okay not to attend something that you are not comfortable doing. Communicate with your coworkers  so they can know what's happening and plan around you not being there.
Nope, I'm going to call my coworker and ask him whether I can leave my spouse behind or not.
Spouses are expected to spend vacations and recreational activities with one another. If you're trying to go on a trip without your spouse, make sure you talk to them first and get their permission before making plans. Otherwise if they find out then they will be very upset.