If it doesn't return,
It was never yours.
And if it doesn't even realize that you have let it go but is busy watching tv,
Then you are probably married to it

It is possible to find contentment and completeness within and thus be able to give love unconditionally, trust what you put out will come back to you and not be attached to how it comes back.

I didn't say that I would be able to limit my attachment for a long time, though I've already tried it in my life (unfortunately). But then the reason was because I was afraid that my significant other was not as involved in our relationship as I, so actually it was a way of self defense and I don't think it was healthy.  I know that limiting yourself when you're in love and trying to believe that it comes naturally when it doesn't leads to the situation when you mask your own unhappiness in the whole situation.You think that it's safe but it isn't. It's just pretending that there's no problem with trust or openness. And I know it. When writing the sentence "the less you attach to somebody the less you suffer if they leave" I was thinking about the situation in which people love each other so much that they don't think about own happiness only. There are rare cases in which people say that somebody left them and are now happy with somebody else, so it's good because it's what matters the most. But it's good only if what they say is really true for them, if  they really can think like this and are not cheating themselves only because they are so unhappy that they don't know how to console themselves for their loss. However, I think that this kind of love requires maturity and even some sort of spiritual development which allows to let things and people come and go. So you may suffer but you accept the fact that somebody left and you know that it just must have happened.

I think that it's good for this discussion to divide attitudes towards attachment into three separate attitudes. First is forcing yourself to limit it because of fear, second is when it comes naturally because you really are not involved in relationship (in this case you probably don't respect somebody else's feelings), and third is when you love someone very much and this love lacks selfishness so you let the paticular person be happy even if not with you. And I was writing about this last case.

The difficulty in giving yourself completely is that both parties have to give.  When you are in a relationship where you have given your all and the other has not, it sooner or later fails.

To love is to give completely.  When it fails is hurt and despair.  But then life is full of those experiences for us to learn and grow.  

When we can truly say we have loved and lost, then are we complete in our love.  We can only be responsible for self and that means we love completely, even when not reciprocated.  But even love dies when it exists in a vacuum without return.

It takes two to tango. One sided relationships are doomed to collapse.

I heard an aunt of mine saying she loves dancing cause you can't be in a bad mood with your partner when dancing, or you wouldn't be able to dance.