I think you made the absolutely sane decision in the situation, and that L and her father are delusional if they thought you would give them that info! I am glad you sent the letter with info not to contact you - you are better off with-o them in your life. I know I am better off having cut my gfgbro from my life and my kids/husband's lives, and so are they. My parents still try to get us toghter, esp as we just moved close to them (6 min walk instead of 20 min drive) but I am not budging at all.
This isn't a decision with-o cost, but it surely is the sanest decision possible. I am glad that distance has made this much easier. I feel sorry for any children L has. Hopefully her new h wil realize what she is, and get spend the $$ to get full custody when they divorce.