Say sorry to your 'enemy' because you are really saying sorry to God. Go and do it. Go with your head held high, giving them eye contact, go there with dignity, and say it like you mean it. Account for what you can account for. God does not ask you to account for what they are expected to give. But, likewise, have no expectation of them.
God already knows us inside out; our strengths and limitations. Even with these issues, He has given us a solution in 2 Corinthians 12 v. 9-10 which reads: