I have 2 beautiful Christmas cactus plants that are budding, and I went to water them and found lots of tiny white bugs w/ little antennae crawling around in the soil! They don't seem to be on the plant itself. Anyone know what they are and how I get rid of them without hurting my plants? Thank you so much.

Sounds like Springtails. When the soil is watered, the little bugs will run around real fast over the top and you might see some jump a little too. They won't hurt your plants at all. They like to play in a moist environment and they will feed on decaying material in the soil.
So after flowering, let the soil dry out more. You can also hold each plant steady in their pots, the turn it upside down, spilling out almost, or half of the soil, then replace with new soil. another thing you can try, next watering time, flush the soil so they (bugs) get flushed up over the sides, you might have to replace some of the soil, or, add a few drops of mild dish soap to the water. In the spring, if you still have some, you can change the soil and then water a little less.