Can a Catholic answer this question I have about forgiveness?

I was reading this story about this wondeful man named Dr. Petit.

Dr. Petit's wife and two daughters were brutally raped and murdered in their house during a home invasion.

The robbers then burnt down the house and left Dr. Petit for dead.

Dr. Petit survived.

He has not forgiven the killers of his family and wants them to get DEATH.

Will your God send Dr. Petit to hell for not being able to forgive the killers of his family and wanting them put to death???

If Dr.Petit cannot forgive them, how can God forgive him?

Matt. 6:14-15–If you forgive those who sin against you, your heavenly Father will forgive you. but if you refuse to forgive others, your Father will not forgive your sins.

My God is an awesome God.

sooo calm down

I'm not a catholic, however I feel very strongly to response to this question.
There is no doubt unforgiving is a sin. No one has under gone the physical and mental abuse that Christ suffer (no one). do not believe the pictures you see and movies, Christ was hanging on the cross stark naked, he was beaten, ridicule, disgraced and killed. yet Christ said in Luke 23:34 "Father, forgive them: for they know not what they do. If Christ can forgive who knew no sin, who are we who are sinful think our hurt is so great we cannot forgive. You can not enter kingdom of God with unforgiveness in your heart.

Can a Catholic answer this question I have about forgiveness?

awesome god, heavenly father, hell, home invasion, killers, mental abuse