Yes! When you move to an assisted living community, you are renting a home or apartment. That property is yours and you may have as many guests as you want, so long as you are not disturbing any of your neighbors.
You may have adult children or other relatives who wish to visit you during the holidays or random times in the year. They would be more than welcome at an assisted living community, and they could even mingle with the new friends that you have made.