Don wasn't gay. He was bisexual. And Nami went into the relationship with honesty and sincerity. She never said that she will remain just friends with Don. She clearly stated that she was still in love with Don and wanted Don to eventually fall for her. It is Don who keeps leading her on even after knowing her intention. Don should at least have the courtesy to tell her that he will never love her. And that he cheated on her.
They are then both stupid.
Only stupid people are capable of love.
She knew what she was getting into. I am not going to be sad or angry for her. What the hell was she hoping for? For him to stop been gay?