My partner is a nicer person on it too. He is sweeter and talks to me lovingly. He has repeatedly opened up to me on a deeper level, telling me things that help me to understand him… all while on it. Off it, he is on a prolonged serious come down, which makes my life hell.
As far as I can see, the frequency of taking it has messed with their brain chemistry so much that they only feel truly good and relaxed etc when on a high. The rest of the time they are on a low.