Can i count on him as a friend?

My male friend is very forgettful i dont know if other girls get this with boy/girl friendships but hes always oh ill email u on monday and forgets so most of the time its me emailing him. r. When i see him he asks me i should go over his flat sometime to watch a film and hell say ill email u monday which he forgot as usual to arrange a date so when i email him he doesnt reply. I know hes forgetful and as we work in same office but diff departments his one is more busy than mine so dont always have time. I feel alittle offended even though i shouldnt as we go to lunch and he seems to enjoy my company. He can also be hot/cold hell be really tactile and then other times moody with me. Anyone else have this problem. He sends out mixed signals as when he sees me he follows me round like a lost lamb. Like for eg we caught the bus and just literally followed me round the shops. He is worksworthy and actually appologised the once for not replying to my email which he rarely does.