@GuitarLegend I think her friend was giving her good advice! You need to care about yourself when you're in a relationship - it can't always be about the other person, even if you really love them. If someone has legitimate complaints and is really suffering because of their s/o, then they can break up with them. It's perfectly valid not wanting to make yourself suffer when you don't have to. That's not to say you shouldn't try your best and give it your all, but you have to think about your own happiness, too. If a relationship becomes a loop of forcing yourself to do things you don't like and ultimately being unhappy most of the time, it's perfectly fine for you to leave that relationship.
She cares enough to stick through it, and that's great! But it's also okay to decide that you don't want that for yourself. It takes two people to make a relationship work - they should both be happy!