What do when you love someone who love someone?

Wait let me get this straight. You love someone. That someone loves someone else. But that someone else loves you. Then, that someone else fell out of love with you and fell in love with the person you love, which is someone. So you're asking how do you love someone that's mutually in love with someone else? Well. I don't know. You just love them. You just can't let them go if it's a real love. But if you're annoyed of it, you can go and try to get over it by find someone else -- or move to another state xD you can also try to steal that someone so that he or she can love you. or you can do what 87% of people who are in your situation do and just stay with them and act like everythings okay-- but of course you would be completely hurt. Your choice