If you are on Facebook there are several very good support communities for those with lqts. I would suggest looking into those as you will find many in the same situation as you who will be able to offer advise/support.
If you have LQTS you should be under the care of an EP and not a cardiologist. Have the episodes been caught on an EKG and confirmed to be PVC's? PVC's are benign and are not a symptom of LQTS and will not lead to vtach.
I think your anxiety is making your skipped beats worse. Sometimes, in my experience, they take on a life of their own. If you can meditate, relax, breathe slowly, it can make a huge difference. I can't comment on the long qt, but if your doctor has cleared you of heart issues, working on the anxiety may help your overall condition. Avoid large meals, spicy foods, carbonated drinks, caffeine. All these are triggers for me. Good luck to you on this -- it can be managed -- don't lose hope.