My boyfriend got into my Facebook and changed my password without telling me?

[beauty]

I put the pieces of the puzzle together today and found out my boyfriend somehow logged into my Facebook, looked through my messages -- he responded to this one guy who messaged me, but then deleted his response so that I wouldn't see it & accuse him. But I still ended up finding out he was on my account. Then i tried logging into my account with my password & it said "You changed your FB password at 8:03am" and i was SLEEPING AT THIS TIME! so i know it was him!!! He has done something like this, but denied it to the T when I came forward with it…he wouldn't admit it was him (referring to something else).

I want to ask him, to see if he comes clean and is honest, but if he lies I feel like he will deny deny DENY it. This bothers me...