You're right, I don't. Because let me put it into perspective for you. Raven was in Mount Weather and only just made it out. My girlfriend was in that mountain. Monty's mom could have been, and if she was? She's dead. They're all dead. So there isn't a single reason I can think of where staying with the Grounders makes any sense at all. They can't be trusted.
And I know you haven't done it yet, but you will. So sorry if I'm having a hard time, but I tried so hard to bring you home, Clarke.