Jared and Evan are left pretty open ended by the end of DEH, and I honestly believe it can stay like that, since the story doesn’t focus on their relationship, it focuses on Evan and his relationship with the Murphys.
I know Will says he believes they never make up, and while I don’t agree with him, it still makes sense. Sometimes, you lose friendships along in life, especially after how they both treated each other. Does that mean they never saw each other again? Not necessarily, since they’re family friends. Being them, I doubt they’d tell their parents about their falling out, and may have to put up with each other when they’re parents decide to visit each other. The two of them just never took the opportunities they had to make up, things remaining awkward or tense between them.
In my mind, I believe they make up after time. Both hurt each other pretty badly by the time Good For You happens. In Finale though, we see how Evan grew as a person, someone once who was so scared to even have a small conversation with the girl he liked now has the courage to meet up with one of the people he deeply hurt, so I believe Evan is more likely the one to reach out first to Jared if they were to make up, while Jared would most likely try to push him away. With persistence, I think they could eventually make up, with both of them realizing how badly they hurt the other.
And then there’s the angst Au or whatever my sister and I came up with where instead Jared and Alana don’t get a happy ending, with Alana’s mind snapping and Jared dying from drunk driving, and Evan never hears from either of them again.