Look man I have to honest with you, you seem very passive aggressive and controlling in that letter. Also, there is mention of abuse.
She was raising 4 kids at the time and wanted to take a trip to NJ with her friend and take a break and you made her feel guilty about it. How about honey you know what you take care of the kids all the time you deserve a break why don't you go spend the weekend with your friend.
Again, I was guilty about being P/A and laid some guilt trips in the past. I am just explaining what I hear when reading the letter so you can learn from it and not make the same mistakes in the future.
Below is a quote by Thich Nhat Hanh that is one of my mantras now:
"You must love in such a way that the person you love feels free".