Have you considered writing a letter? A letter would allow you be more contemplative about what you want to say. Alternatively, you could write a letter as a way to think through what you want to say and then visit him in person to explain and to apologize.
When it comes to apologies, sincerity is key. It is the best “general formula” you can follow. Sincerity is defined as “the quality or condition of being genuine, honest and free from duplicity or hypocrisy.” The opposite of sincerity is insincerity. It is defined as being “phony or dishonest, not showing one’s true feelings.”
Whether in person or in a letter, the more sincere you can be with your apology and explanation, the better. You can’t go wrong with the truth. You mention, in your writing, that you don’t have much in the way of people skills/communication skills/social skills, etc. These are all things that you can learn and counseling is the very best place to learn those things. Talking to a counselor or therapist before talking to your GP, would be very helpful. Please take care.
Dr. Kristina Randle