It’s always difficult to accept, but if received with humility, and a desire to improve ones character, it is very helpful.  Only a fool does not profit when they are rebuked for their mistakes. 

Proverbs 27:5 associates constructive criticism with love.

I struggle with criticism, especially when I think it is not given with the right motivation and in the right spirit.  Yet even then, I am slowly learning this:

1) Respond but don’t react; committing the matter instantly to God and asking Him to remove any resentment or counter-criticism on my part and teach me any needed lessons.

2) Remember that we are all sinners and that the one who has criticized me doesn’t know the worst about me.

3) If I have made a mistake or committed a sin, humbly and frankly I need to confess it to God and to anyone I may have hurt.

4) Be willing to learn afresh that I am not infallible and that I need God's grace and wisdom every moment of the day to keep on the straight path. 

He who profits from rebuke is wise.