It's now five years later and I am still friends with both. You get a new and even prettier girlfriend, or hang out with your friends more, or get into jiu jitsu or knitting. Because, again, you're declaring to an old friend that you're prepared to disregard his feelings.
Of course you can. I want you to know that I have spent several hours now scanning the back issues of Tiger Beat magazine, and as far as I can determine there has never been a standardized "Girl Code of Ethics" that experts have been able to agree upon. I was friends with a couple in high school, though always closer with the guy. Now, if you're sure that this is not you, that this is Real Love you're looking at, then what you have to do is tell your friend what's up. Read our community guidelines here.