Mt fiancee likes some metal, a few classics like ac/dc or a little Black Sabbath, but mainly more melodic power metal like Kamelot, Nightwish, Leaves' Eyes, Masterplan, Edenbridge, etc. I like most of those bands too, so if we're driving or listening at home, we stick to that stuff, and when I'm working/on my own I listen to other heavier/more obscure stuff that she's not into. We've gone to a few shows together and had fun; neither of us "live the lifestyle".
My concern has been more about collecting, as I do get kinda geeky about 80s metal vinyl and will on occasion bid relatively high for a record from my want list. This has not been a problem though; as long as the bills are paid and we're saving some money, she actually encourages me to go after my want list items when I find them

Gotta love a woman who tells you, "I think you should bid a little higher on that Hammer Witch EP"

"I'm sorry Sam, we had real chemistry. But like a monkey on the sun, our love was too hot to live"
-Becky