You need to cultivate emotional states in the same way that you cultivate mental structures. Art, music, literature, and memory can help with that, but it takes just as much practice as the thought structures do. Don't try to bring the emotions into the structures yet -- first you need to be able to experience them on their own. Find things that rouse your emotions, and let yourself feel the emotions they waken. That's how you start. Going beyond that? The education of the emotions is a complex process, and to some extent you'll have to feel your way there.