It can be tempting to try and warn the poor unfortunate woman whom comes along after you about the Baron of this particular Boneyard of Broken Promises. However, please do not waste your energy in doing so. She will have to learn on her own much like you did.
Don't you recall how his previous exes, his family/friends, your family/friends tried to warn you about his grandiose promises and his tendency to break them on a regular basis?
Did you listen?
Of course you didn't.
Because you needed to believe that his past behavior of breaking promises was a reflection of his most recent Ex. If She would have only kept him happy, he would not have broken his promises to her.
Ironically, once upon a time, She believed the same thing about her predecessor and it took her years to navigate herself through the Boneyard of Broken Promises back into the Land of Sanity. Follow her example and just keeping walking towards the light...do not look back.