Internal Family Systems (IFS) seems to overlap with Zen in one very significant and helpful way: it provides a system for disidentifying from our own challenging emotions and becoming merely aware of them. The surprising part is that we become unburdened by that which we simply notice, versus that which we "are". In the end, it seems increasingly true to me that the less "self" is present (and the more the contents of experience can just do whatever they're doing) the lighter and freer we're going to feel.