expecting in relatioships

there is onething for which i have never got any correct answer to..is it alright to expect in a relationship??
its so easy to expect from my mom..whether i get what i expect or not i dont feel very bad..but why is it so different with friends??these expectations only lead to dispointment and misunderstandings..and inspite of that if we do expect and its not fullfilled why does it lead to so much of pain??

when i can expect in one relation why cant i expect in others??
its so confusing..if we dont have any expectations of any particular person in our life then it means that person is not close to our heart..yet to maintain that person close to your heart and to not to let any sort of distance grow between us its essential that we dont expect much..and if love is all about loving the person as s/he is then why do we expect anything at all from them??then how does one expect the "right" way??
and if you reverse the question and ask me back if i am interested in realising other people' expectations i think in a way yes..i do consider them atleast until it dosent bother me..but most of the times its so difficult to understand what exactly the other person expect from us..

my biggest doubt is that is an ideal relation that which has a lot of expectations and fulfillment or that in which there is none??
this is onething that really bothers me..should i expect anything from ma friends..if no then i just dont feel close to them..
if any of you more enriched and experienced ppl have any idea please do let me know..which is the ideal way for a perfect relationship