Common cold sores are usually caused by the HSV-1 Virus - most people (8/10 people) have contracted this virus but fear not it usually only appears when you're immune system is weakened or you feel run down.
It is only infectious when you feel that tingling sensation and when it has developed into a lump.
Yes cold sores are a part of the 'herpes' family but HSV-2 is the only kind which is contracted sexually - These are the ones to worry about.
Source:
http://www.nhs.uk/conditions/Cold-sore/ ... ction.aspx
Even so I don't blame you for calling it off as I'd probably of done the same, just hope you had a convincing cover story so you can contact her again when you're sorted
