Hi Tani-Sue
I believe that you have the potential to be much more flexible. Robert (husband and webmaster!) used to offer this analogy. The frequency of your yoga practice is like spreading butter from the fridge. The more often you take the butter from the fridge the more spreadable it becomes, the less time it spends in the cold getting hard again. So going to yoga as often as you can, can only make you more supple and flexible. You get that grease and oil change that makes your movements more easy, more open.
There are specific poses that are great hip openers. Your teachers MAY know some that you can use. I have suggested in a number of posts to many readers to practice some long duration poses where you enter and stay in poses for a number of minutes at a time. After a Hot Yoga class is the best time to practice these because your body is already so warm and surrenders more, resists less. If you have the opportunity to stay after class for 10 or so minutes and just simply choose a couple hip openers for each side and stay in the 2-3 minutes each then this can make a difference to you. Maybe (like a lot of Hot Yoga studios) your studio offers yin yoga classes or specific hip opening classes.
Namaste
Gabrielle