Hi Marioman
You said in your earlier posts that this girl craves attention.
And she is getting it from you, isn't she, even though it is over between you?
You are not sad or angry over her engagement, which shows that you are coming to terms with what happened.
All the same, she
was planning to move in with you; she
did break your heart; she changed; she let you down.
You are bound to feel something about this ~ and it's not surprising that you don't feel 'overly happy' about it.
I think that your reaction is probably normal.
The person she was ~ or you thought she was ~ will always have a place in your heart ~ even though your head knows that you are better off without her.
The best response you could have given, in my opinion, would be to congratulate her on her engagement and leave it at that.
Is that what you did?
It's over. She's engaged. You are getting over her.
Accept your feelings of confusion as normal and then get on with enjoying your life.
Good luck