In the course of my life I've done many things that I've later had to go back and ask forgiveness for. There are times that we all just fly off the handle or say things that we would never have thought we would ever say, that's because we're human and try as we might it's impossible to be perfect, period, especially every second.
What do we do when the person we need to apologize to is no longer in our lives or maybe has passed away. The logical thinking is that we've lost that opportunity and will never get the chance. But, we know that God is God and any thinking we think is logical in this world might be completely illogical to Him. God is all about forgiveness, He sent His Son to die on that cross for us and what did Jesus say when He was suffering such excruciating pain...He said, 'Father, forgive them, they know not what they do'. Wow, Jesus was asking for immediate forgiveness for those that had done the most despicable things and He was at that moment suffering at their hands and yet He asked our Father to forgive them, such wondrous love!
There have been some times in my life many, many years ago that I have suffered at the hand of another person, I can assure you that my thoughts were not of their forgiveness, they were about fear, pain and hurt for myself. A few years later I realized that although the person had not asked for forgiveness I needed to give it, not for that person but for myself, how could I possibly obey Him if I was unforgiving and holding on to pain and fear.
Incredibly through His Grace alone I was able to let go of that fear & hurt and forgive that person, they may never know they were forgiven because I may never see them again but I know and most importantly the Lord knows.