conflicting emotions!

i notice that emotions and the resulting behaviors of people always tend to be conflicting.
just consider this case
when do we like/love a person? when we like everything or rather most of the things about them.and why do we get angry? when people don't fulfill your expectations.and who are the people you get angry with?the same person you love a lot and you are close to.
the very same person about whom everything you liked the same person is the center of your anger..i always used to ponder about this cos i always get angry with people who are close with me and fight a lot.
we are afraid to express our emotions to some x who doesnt mean anything to us but end up hurting loved ones.why does this happen? do we have the tendency to take loved ones for granted? or is it that we tend to vent out all our depressions and disappointments on them cos they are stuck with us?isit the simple privilege in thinking they will understand us? we are so cautious as to not to hurt the feelings of someone who doesn't make any difference to our lives but tend to slice the heart of loved ones with our knife like words...
what causes the change in us?i am clueless.do we stop considering the loved ones emotions or are we too naive to take them for granted?or is it the over protectiveness and affection that makes us to behave like this?
consider the case of being hurt..why is it that we get hurt by someone who doesn't mean anything to us at all and tend to get hurt ourselves and sulk?so many emotions and so conflicting in nature.the way we have to react to loved ones we do it for complete strangers and the vice versa.why does this happen?
may be we are forced to hide our emotions from strangers cos the world is like a wolf to pounce on our vulnerabilities , we cannot displease our bosses.true...but our loved ones??? are they to be used as buffers? or are our family sentiments and values decreasing..my mum used to tell me tolerance is decreasing with every generation.are we starting to prove it???i hope not.
i only hope this post will make to a difference to at least one person and their loved ones.and if it does...what else but peace :) !