No one is forced to celebrate Christmas.
In fact there are billions of people around the world who don't.
Mother's Day, Father's Day, and Valentine's Day are all days chosen by mankind to take time out to acknowledge particular individuals.
Christmas in my opinion is in line with those other holidays where it is just a date that was "chosen" for Christians to honor the birth of Christ. All holidays are essentially a "time out" to acknowledge.
I don't think anyone truly believes Jesus was a Capricorn born on December 25th! It's just a date assigned for the celebration.
Nevertheless because no one knows the exact date of Jesus' birth doesn't mean Christians should feel obligated to ignore the chosen date simply because it coincides with the traditional "Winter Solstice"
In fact December 25th was chosen because people were already celebrating pagan festivals during that time of the year.
Christmas was a "me too" holiday. Most super religious people make a bigger deal out of Easter and the events of the crucifixion.
Of course one could argue against celebrating that as well since there is "The Easter Bunny" and college spring break vacations! LOL!
Just because multiple events or traditions are taking place at the same time doesn't mean one of them should be discounted.