What a grand old Irish name! :) My first name is Patricia and my grandparents came from Ireland and my dad always told everybody I was named after St. Patrick.
Dealing with cold sores can be so miserable and I'm sure you know they are extremely contagious. Dealing with a virus isn't easy to knock out of your system. If you're prone to cold sores I'd suggest you start taking L-lysine. It's an amino acid used as a supplement. It can heal a cold sore or prevent it from forming. It's a really good preventive measure. Take 2,000 to 3,000 milligrams a day to keep cold sores away and double the dosage if you feel one coming on.
Another good remedy when you feel a cold sore forming is to take 400 milligrams of Vitamin C a day. Just drink a big glass of orange juice every morning or you can take supplements.
You could also try eating two cups of yogurt with live bacteria a day to prevent cold sores from forming. The active bacteria seems to boost the body's immune system response.
Another little tip, get a new toothbrush as soon as you suspect a cold sore is coming on. This may help the cold sore from breaking out. If you caught it too late and the cold sore forms make sure you buy a new tooth brush again once it clears up.