All of them, but for me it was mostly the friendship. When we split for a few months (intending to be for good) it killed me...we'd been together 5 years. More than having someone to cuddle with or have sex with, or any of that...I missed having my best friend. We did everything together, shared everything, talked about anything...he was (and is) the only person I've ever felt truly comfortable being 100% myself around. Evidently he felt the same, and we couldn't stop contacting each other and worked things out. But those few months were so hard on me.