Hello, RUSS1075. There are some rose shrubs that are like that but if your plant did not exhibit this problem for the last 7 years, it is hard to believe that it is one of those roses with naturally weak stems. It sounds like you may need to keep an eye for further symptoms.
Test the soil to make sure it is not getting too dry. Review the weather in your area to see if it has been very windy as this dries out the leaves and can cause a wilted look (but they should recover if you water it). Also check to see if there are pests underground by keeping an eye on plants near this one. Some pests may be damaging the roots. Over-fertilzing could also cause thin weak stems so stop fertilizing if you have been fertilzing a lot, and monitor the plant for the next 6 months. You could also get a kit that detects too much nitrogen to see what it says. Check the soil with the kit to see if it is also defficient in phosphorus or potassium.
Just a few questions that I was wondering about... Do you know the name of this rose? Did the problem just start recently or it been going on for a few months? Is the shrub getting as much sun as it used to in prior years or is it getting more shade? Does it look as if it is streching towards the sunlight?