Don't worry your potted rose will be easy to transplant during the winter or dormant months even if it still has  leaves on the healthy branches. I suggest you remove the rose from the pot and shake off most of the soil. Then you can prune back any of the larger and thicker roots that make the rose hard to fit back into the pot or find a larger container for the rose. Winter is also the time to cut out any dead, diseased or damaged wood. You can shorten all the branches by at least one third or do a severe pruning and cut the back the canes to two foot stumps. Next use potting soil with some organic compost added to repot the rose. A mix of 3 parts potting soil to one part compost is about right. Be sure to add some slow release plant food like Osmocote as roses are very hungry plants. Replace the rose so that is growing at the same level in the soil as before. Water in the new plant, place in a sunny spot  and you should see renewed vigor this summer. Keep growing, Marianne Binetti