Why did he leave me and how to get closure?

About 5 days ago my boyfriend of 5 months broke up with me, saying that he just wanted to be friends and wasn’t ‘feeling’ our relationship. He said he was sorry, and that I didn’t do anything wrong. This was a total shock to me, as we had been perfect just the day before and were very happy with each other. We both had strong feelings for one another and our relationship was not problematic/rocky. He’s 16, I’m 15. He was always telling me how much he loved me and needed me, was a bit clingy, and was honestly not just a boyfriend to me, but a best friend.

The night he broke up with me I asked if we could talk and he coldly told me that there was ‘nothing to talk about’.

The other night he had texted me asking if I was at school the day after, and that he had been looking for me and if I saw him. I said no, as I had been at school but hadn’t seen him. He replied with an ‘I’m sorry’. Last night, I texted him a simple ‘Hey, what’s up?’ to try to get to the bottom of this. Our conversation went pretty much nowhere. I have not talked to him or seen him since.

I was really upset about it, as I was really happy with this guy and truly did have feelings for him.

So I’m wondering, what is the REAL reason he broke it off with me (I don’t see how we could have had what we had and gone through what we have and just end it that easily)? You would think maybe ‘another girl’ (and maybe I’m just in denial), but with my last ex (who liked another girl), it was somewhat instictual and could see it coming. He was always talking to her on myspace, texting/calling her, and hanging out with her. I already knew about the other girl and felt him getting disant, so I broke it off, and they went out a week later.

With my current (ex)boyfriend, I just don’t see that as he’s always been hanging out with/calling/texting ME and was never distant (albeit he was very moody at times, but this has always been a thing of his). This breakup was so abrupt and sudden that I’m still in shock.

It doesn’t seem like he wants to talk to me at all, but I think I deserve an explanation. He was so good to me in our relationship, never cheated/treated me with disrespect/lied/etc. but even my friends have been talking about what a jacka** he’s being.

Some of my friends think he broke it off because he was afraid of getting hurt. He once thought that I was cheating on him with my best friend and sometimes thought I wasn’t really ‘into him’.

So, down to my questions.

-What do you think is a possible reason for him leaving me?

-How should I go about initiating a conversation so I can get some closure? (should I even try?)

-Do you think it’s possible that he still has feelings for me or that we would get together again? (is it even worth it?)