Honesty with yourself begins where your favorite explanation stops being useful.

Everyone keeps a preferred account of why things are as they are: the timing, the other person, the circumstances, the way you are built. Some of it is true, which is exactly what makes it durable. The useful moment comes when the familiar explanation has been offered again and nothing has improved, because that is the signal it has finished doing its work.

Take the reason you give most often and set it aside for one problem. Ask what you would look at if that explanation were unavailable. Start there, gently.