I think you should get this cultured the next time you have an outbreak to make sure that you have hsv2 on your finger, and not hsv1, and have hsv2 genitally.
Whitlow is typically - not always - hsv1. In adults, it can be from autoinoculation (infecting yourself in another location) during your primary hsv2 outbreak. This means that you touched an outbreak with your finger that likely had broken skin.
Regardless of which strain you have, you really only need to be careful when you have an outbreak. Herpes only sheds from mucous membranes, and the fingers don't have that. If you have an outbreak, it's a good idea to cover it, and be really careful not to touch anyone else that has broken skin or their mucous membranes - mouth, nose, genitals (don't use that finger on your partner's genitals during an outbreak, for example).
You could have had this prior to your partner, and just now gotten outbreaks. You may never know how you got it.
Hope this helps!
Have you ever had another partner besides your current one? It's possible that you got it from a previous partner, and never had symptoms.