I think you've answered your own question with the last sentence. Some people are really insistent on everything matching and others mix. If you've never been comfortable with mixing metals before I'm not sure you'll ever be... and that's totally fine. Another option is to sport one or two pieces of jewelry that contain the two metals?
I personally love mixing metals because I think when done right it looks very 'naturally' chic (as though the person doesn't try too hard to look perfect if that makes sense). I have a silver and gold ring for example that I basically wear daily which along with my wedding band that is diamond/platinum, kind of helps to tie everything together. I'll be honest though, I basically wear the same jewelry everyday so maybe I'm not a good example. Also, I may not be as chic as I would like to think