Yes i would say love and passion are very important in a relationship, but it's a two way thing REC-NAC. Did you try and spice things up yourself , or did you leave that side of things to her ?? Also did you talk to her and try and find out why she was maybe feeling less passionate than yourself ?
I'm not having a go at you but sometimes it's hard to feel sexy when you're up to your eyes in washing and ironing.
Obviously you'll know yourself if you can honestly say you gave the relationship your all, if so, you probably did the right thing walking away.