The overall energy feels very karmic to me.
He has sun-saturn conjunction falling on your pluto, so that is hard. You were meant to transform him, perhaps help him deal with that conjunction as it is hard on the self, identity, ESPECIALLY in libra. Saturn is exhalted here, but Sun is in its fall, so Saturn is even harsher on the Sun.
His chiron on your Jupiter does speak of healing again, but it's a tricky conjunction, cos your Jupiter might magnify all of his past hurts. Since both in Taurus that might actually take it down a notch.
With Venus opp Jupiter these is a theme of too much drama, blowing things out of proportion, and in some way this is what brings you together. You both have this conscious or subconscious likes for drama and everything BIG and dramatic, very Sag/Jupiter sort of love, but at times it gets too much, so you gotta leave it. '
His Asc is hooked on your Neptune. You can help him a lot spiritually and psychologically, but it depends much on him how much he can handle that help.
This whole relationship is very... hm. How do I say it.. it's almost like mother-kid. You are trying to heal him, he is trying to heal himself, but nada.
And I think the nada comes from the lack of Node aspects. However, this is interesting. His Mercury falls on your N.Node, and your Mercury falls on his South Node. This is SUPER karmic. It's all about communication. He still hasn't learned how to communicate his thoughts, feelings, emotions, ideas, and it's still scary for him apparently if its on and off. While you have developed that skill in a past life with him, and you should be more inclined to sharing, talking, communicating, should be easier and more comfortable for you. But things on the South Node are not meant to last for long. And generally the lack of other node aspects is what makes me think why this is not stable or lasting.