Is love acceptable in friendship?

Friendship is often termed as the most beautiful relationship out of the rest. Some even call it the basic building block of every relationship. Friendship also signify care and support at the time of need. But there is a marginal difference between love and friendship with the definition of that margin still being a mystery.It has turned out to be a common trend of late that best of pals, at some stage, fall for each other. If this happens at two ends, then it turns out to be a win win situation but if this feeling creeps in at one end, its then that the real trouble starts.
And who else to write on the situation mentioned latter than someone who is going through it all. It really hurts when we get to know that the person to whom we are dying to talk to isn't at all interested to talk to us. And it hurts even more when we get to know that, she in her terms, was doing a favour to us by not talking as she didn't want to hurt our sentiments and feelings. And then it sets the temper rising when she tells that she still cares for us even though she used her words at free will irrespective of their slang and decency.
Now I would like to ask that love is supposed to be there in a relationship only and only if the two concerned people get along with each other very well and are able to understand each other i.e. they share a high comfort level with each other. And this generally refers to friendship. So summing it all up, love can hold when you can be a friend with your partner. So why is it considered a taboo, breaking of faith or deception in friendship when a friend falls for his/her friend? If friendship is must to sustain love then why isn't love acceptable in friendship? And why does one who falls is punished with mental tortures for getting into feelings when it is well known that feelings set in by themselves or by default. One has got the power to only hide his/her feelings upto a certain limit and rest there is nothing in their hands.
So I would like to conclude this with a question asking for your opinions about the same (especially the comments or explanations of girls). Do you think love in friendship is acceptable or do you think that one who falls for a close friend is liable to be punished for this?