Is Confrontation a healthy part of a relationship? As opposed to a relationship where both party are afraid to hurt each other's feelings, so they never confront each other?

Yes it is. Like you said, the fear of not wanting to hurt each other makes them keep things in their hearts which builds and become blocks that become hard to pull down
If there is a matter, discuss with your partner, sort it out once and for all no matter the consequences
A problem said is a problem solved
If you don't tackle it, you will go on hurting which might even end the relationship without the other party knowing why
On the other hand, the second party might not even know he is hurting you
Remember, two cannot work together except they agree

mabell:

If there is a matter, discuss with your partner, sort it out once and for all no matter the consequence[/b]s
A problem said is a problem solved

As much as I agree with you, the highlighted part may be misunderstood . The bible recommended confrontation, but the confrontation must be done in love and humility. We correct in love. But whe. You say "no matter the consequence" I feel it may suggest negative attitude.

[b]Matthew 18:15-17
15 “If your brother sins against you, go and show him his fault, just between the two of you. If he listens to you, you have won your brother over. 16 But if he will not listen, take one or two others along, so that ‘every matter may be established by the testimony of two or three witnesses. ’ 17 If he refuses to listen to them, tell it to the church; and if he refuses to listen even to the church, treat him as you would a pagan or a tax collector. 

@joagbaje and mabell
Wait o!
I have an instance.
A lady is into a relationship with this guy and finds out he is cheating on her
with all the evidences, she confronts him the first time, he does not say yes or no but says im sorry and she forgets about the matter thinking it would stop
it happens a second time after like a year only for him to tell her to stop habouring evil tots
she again noticed after some months that he never stopped dating the other lady
she can't confront him again, cos she is tired of it, she doesn't want to hurt him and she doesn't want to hear his same responce again
At this stage, do u still advice confrontation?

i told her to forget about the guy cos he's not ready for her but she seems to be so in love
pls help me

@Mudley, do you have insider information you are dishing out piece-meal, come'on out with it  

Confrontation usually means No Compromise- No Understanding, it means "We no go gree", it means "My way or The High-way", it means[b] "You are hereby accused"[/b] and If you are familiar with Man right from the days of Adam. the first reaction is Denial and Blame-shifting and God was not being confrontational then . like Joagbaje pointed out, Love and Humility