boyfriend is 20 yrs. older, and schizophrenic but I am in love with him!?!?

My boyfriend is 20 yrs older than me ....I am just now getting to thinking age really might be a factor . Only because things got way weird! We used to have the Best Time Together ! ! Never Ever Fighting , we Had Awesome communication , and we're Always Happy!! And smiling . ...like on a Movie. People were envious of us. It Radiated off us (our happiness ) but then out of know where a few months later he did a complete flip on me, we fight all the time , he Not the same person ! I had to find out on my own he is paranoid schizophrenic, and he fights taking his meds. He gets Very Evil and almost violent and says the Most Evil Hateful things imaginable , , Everything is My Fault , he sees Demon's , and Spirit s and hears them, they talk to him, and he talks back. And he thinks he is Lucifer..I don't know what to do , and I tried Everything ! ! I feel like I'm in a movie or twilight zone...if feel like if I leave he will either be dead or locked away for YEARS!! and I Still do Love him....when he takes his meds as prescribed he is who I fell in love with again ! ! I am at a cross roads and don't have the answers , and Need ur thought and advice . ....