The problem with miniature "grocery store" roses is that they were not meant to survive much beyond Valentine's Day. What you have is a pot of rooted cuttings that were grown in a perfect climate inside a greenhouse and forced to bloom out of season. I think they were designed for those of us who can't stand watching a bouquet of cut flowers die - we are lulled into thinking this is the perfect solution - a bouquet of living, blooming roses!
You are right, roses were never meant to be houseplants, even the ones that were grown with the thought they would live beyond the life expectancy of a bouquet. Start by going easy on the water. As soon as possible, put the rose into a bigger pot. The pot should be big enough to give the plants an extra inch of space all the way around. Find your sunniest window (or think about putting a grow light in your desk lamp) and place the pot on a humidity tray (a shallow pan that is wider than the plant, filled with pebbles or marbles and full of water). Put the rose in a saucer so it doesn't sit in water.
Hopefully, you can get them to survive until its warm enough outside. Next winter, store the pot in your coolest room or an unheated garage.