In the end, Jonas became my brother, Ren and Nona didn't date, and I saved Clarissa. Apparently you could actually save Michael too. Then again, I suppose none of it really matters because it seems like you're just stuck in a time loop anyway!
i had them date, otherwise the same. Seems like there's a new game plus where you can get a better ending to resolve that perhaps but I barely started it and decided to just play something else... Specifically Psychonauts 2. In the new game plus she was getting some deja vu and I had some new conversation options in the little I did.