Sacrifices

On a radio morning talk show some days ago...
Topic: What have you sacrificed in a relationship??
some thoughts...

There are different kinds of sacrifices in a relationship.
- There was an auntie who's taking care of an ailing husband who has cheated on her.
- A man who risk his career, fought with his boss- the rival, over a girl he loves who now becomes his wife and he has resigned from that company.
- A guy who will drive long distances monthly to meet up his love. Sweet :)

There was also a girl who went all the way for cosmetics to appease her bf. Yet, the guy found a prettier gal and dumped her. -_-''

When one sacrifice for a relationship, it's better for happiness and not foolish matters.

As I thought further, many people do sacrifices/contribute efforts to keep a relationship or to maintain love. To make the other half happy regardless of own self.
Can this be a foolish act too?
Perhaps it's just a typical case of one is willing to give, the other is willing to accept.

A healthy relationship will be a balance of such act from both sides.

So...wat is the purpose of one involving into a relationship?
Is it to have a 'decorative item' to be by your side?
Or to have a companion to walk along the path of life?
Or to appreciate the person as who that person is?

Why do we love that person in the first place?
And.....
till how deep can you love him/her?