It all started about 6 years ago in grad school when I was taking a class on CBT and I volunteered to use myself (in front of the class) because I was frustrated with the interactions with my brother. It was that moment that I chose CBT as my theoretical basis and began to apply it to my life. It started out slow with choosing how I react to being stuck in traffic and then started applying it to have I react to other people.
I think I have done a fairly good job at being able to separate what things I can make choices about and which things I have not control over, the latter mainly being other's people thoughts and actions.
Oh, I am certainly not perfect. Far from it. But I sit here at 5 in the morning thinking about how I am frustrated that people do not let go of things from the past and keep drudging it up. Honestly, I wish they would let things go, especially when things have changed. But I realize that I cannot make them do that. I can only change how I react to them. I do not know how I will do that exactly until I am in that position again, but until then I just have to remind myself that I can choose to react differently and find a way for myself to let go of the fact that some people may never let go of something.