can't see myself without him

I know this sounds stupid but its true, before I met him I was very liberal (had a female partner) and just didn't really care about anything much less anyone since all they wanted was screw me over... but I met him and changed everything for him because he showed me something different, had a kid with him... we've been together for 5 1/2 years or so, our son is 4.. about 2 months ago he told me he wants his freedom and I cried like never, now he tells me he just wants to be lonely which I find extremely stupid and selfish (we're still being intimate, it's actually been the best since we met, almost daily) which is what gets me confused!... ive always been there for him, when he wanted to start school, end his current job and get a diff one, etc we're both 28 at this time, he just wants to go out with his friends, come home late... i love him and i feel like I'm begging him not to leave us, dont know what to do anymore..