Help!

So last night my partner admitted to me after being together for 2 years that hes fallen out of love with me. Right now i have so many things going through my head like "is it because im fat?", "is it because im always working and never home?", "does he love someone else?", im basically torn, im so heart broken. We've been talking all day on text and well.. he cant tell me why he has fallen out of love with me because he claims he doesnt know? i just need a little advice on what to do i guess?