<human>: My bf and I had been together for about 3 years when I ended things with him. Our relationship had become strained after I transferred to a new school about 2 hours away (I moved back in January). A few days after ending things, I started seeing another guy [21m]. I was just never really into him, and ended things when he started getting more 'serious'. 

A couple weeks after I ended it with the 'new' bf, my ex and I reconnected. We've been sleeping together for about 2 months and I've been spending a lot of time with him and his friends. But every time I try and discuss the direction of our relationship, he backs off and says he doesn't have the 'energy' for a relationship. This really sucks because I want to be with him. He's the 'one', and being apart from him made me really realize this.

This is confusing and I don't know what to do. On one hand, I want him in my life in some capacity, even if it means a platonic relationship, but on the other hand, it might be too painful to just be friends. (ESPECIALLY if he starts seeing another girl)

Does anyone have any experience with anything like this? Any advice is appreciated.

Summarize the given text in a few sentences.
<bot>: Ex-bf [20] scared to re-commit, (together 3 years, broken up for 6 months). What should I do?