I have a strong desire to write a letter to H. Not to persuade him to dump OW, but to more clearly articulate my thoughts on everything. Emotions were high when we spoke. I feel a strong need to set a few things straight.
Writing a letter to clarify your thought is a good idea. Don’t send it. Put it away, burn it, something other than actually giving it to him.
Like feelings, your thought on this will change as time goes on. However, your words on that paper will not, H will have tangible wording from you, and no matter how well intentioned he will twist them and use them against you or for his own purposes. Your meaning will be lost on him.
You have received very sound advice - Wait.
Your feelings to set a few things straight will fade. Honest.
A plain birthday card is a good idea, and appropriate if you wish too give one to acknowledge his day. Keep expectation at zero, he may or may not respond.
DnJ
Feelings are fleeting. Be better, not bitter. Love the person, forgive the sin.