Sorry, what is bad about his "abandoning" them in the forest? Ron was right about that situation, even if he was wrong about Harry not caring about his family and Hermione choosing Harry over him.

Ron brought up 2 very legitimate complaints: "We are starving, surviving off of mushrooms, and we will die." and "We are dead in the water in our mission and have no leads, and learning the sword of Gryffindor kills Horcruxes does nothing to help us because we don't know where the real one is." If they kept up the Horcrux hunt the way they had been, they were going to get captured and killed. They weren't winning. Harry brushed him off and accused him of wanting 3 square meals and a warm bed and told him to go back to his mummy. The fight escalated, Harry continued to tell him to go, and eventually he did. He asked Hermione to come with him and she said neither of them should go.

He was right and he wasn't being listened to about it, he got in a fight with Harry who told him to piss off and so he did. Where's the abandonment? Where's the betrayal there? If I tell you to leave and you do, how can I accuse you of betraying me? Then Ron proceeds to accomplish more in his absence than Harry and Hermione do while still on the Horcrux hunt, and when he comes back it allows Snape to find them and he saves Harry's life and destroys the Horcrux. They needed outside help, they needed to change what they were doing. Ron was right and he acted on it.

Meanwhile, Hermione attacked someone because they got a girlfriend. The fact that it's meaningless makes it worse.