I continue to recommend the work that Gary Chapman did to create his book, The Five Languages of Apology. Here is another insight from the book.

Apologies Do Not Have "Buts"
 
By Dr. Gary Chapman  
 
This article is about one of the "Five Apology Languages": namely, expressing regret, or saying, "I'm sorry.".
 
"I'm sorry. I feel badly that I hurt you." 
 
Sincere regret needs to stand alone. It should never be followed with "But..." 
 
One man said, "She apologizes, then blames her actions on something I did to provoke her." Her blaming me does little to make the apology sincere.
 
A woman said, "He apologized, but then added that I was acting like a baby and that he had a right to do what he did. What kind of apology is that?"
 
In my opinion, that was not an apology. 
 
Your apology becomes lame when you turn to blame. 
 
When we shift the blame to the other person, we have moved from an apology to an attack. Blame and attacks never lead to forgiveness and reconciliation which are the purpose of an apology in the first place. 
 
When you are apologizing, let "I'm sorry," stand alone. 
 
Don't continue saying anything else. For example, don't say, "But if you had not yelled at me I would not have done it."
 
Leave the "buts" out of your apology.
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