Finding Closure: Writing Thank You Note to Ex-Inlaws

So a couple of years ago, I saw my ex-in laws at a tailgate during home coming at a local football game and my ex mother-in-law greeted me and walked right up to me and gave me a hug, as if all if forgiven and we briefly chatted. A couple of months later, after ny paternal grandfather passed away, my ex and his parents came to his calling hours/vigil at the funeral home, to offer their condolences and supoort (which I fe was thoughtful). So since it seems I am on good terms with my ex-in laws, I'd like to mail them a Christmas card this year and am thinking of including a thank you note, as a form of finding closure. Here's what I have written (names have been omitted to protect privacy):
Dear (Ex-Father-in-Law) & (Ex-Mother-In-Law),
I want you to know I am well.
This is just a little note to express my appreciation to you both.
To both of you, thank you for sharing your son with me. Thank you for being there, your kindness and acceptance of me, your support during the special milestones, as well as your support during one of the most difficult times of my life. Thank you for accepting me for who I am, and most importantly for loving me. You two are some of the greatest parents. I will always be appreciative of everything you have done for me. Also, I wanted to thank you for your presence and offering condolences and support after Granny and Pop passed away, it was deeply appreciated.

(Ex-Father-In-Law,
Thank you for your kindness, wisdom, and your great sense of humor during difficult times. Your sense of humor has always lit up the room.

(Ex-Mother-In-Law),

Thank you for being the kind, compassionate person you are. I miss you and I can still recall your small gestures of love, kindness and acceptance of me. Thank you for all that time you listened when I needed to vent & a shoulder to cry on and to encourage me and pray for me. I am forever in your debt for the kindness you have shown me.

I also want to say how sorry I am, I hurt (ex-husband) and you both. Looking back, I see the changes I could of made, including better communication and respect. I wish things could of turned out differently and we could have made things work. I still care about him and always will, and wish him well.

Finally, let me express my wishes your well-being, good health and happiness for both of you. You deserve nothing less and I hope God continues to bless you in your lives.
Sincerely,
(My real name)

What do you think?

I think that is sweet and well written. My ex in laws-albeit brothers and sisters, still consider me and treat me like family. And granted things didn't work out between myself and their brother, that's between myself and him not them and me.
Life is short, I'm sure they'll cherish your sentiments.
My maternal gram still asks about my father and my parent's divorced when I was 10.

I think what you wrote is very nice and if they are as nice as you talk about in your letter then they would appreciate receiving that letter.

I think it's wonderful, butterfly_angel. If I were a parent, I'd love it. Go for it! Sending many hugs to you and your family