Thank you for your question
I feel like this might be a fresh start to a friendship. Some times people try to connect as friends but it doesn't always work out right away.
He might be looking to start over so his wife invited you over to the party.
People change and he might need you as a friend. I feel she invited you because her husband probably wants to be your friend but does not know how to re-introduce himself. He probably thinks he had so many chances to be your friend, but not feels like he lost his opportunity.
It would be a good idea to go, but if you feel that you do not want to, I would kindly say that you had plans.
I am sure she would understand.
Because you did not tell her that you were going you do not have an obligation to go to the party.
You also do not have to tell him you are not going. But if you wanted to tell her you couldn't go that would be fine as well. I think he might have wanted you to come to get a second chance at friendship.
Her husband might have mentioned that he wanted you to come so she came over last minute to invite you.
But you are in no way obligated because it was last minute.
If you do not go I feel like his wife will just assume you already had plans.
Does he wave at all when he is outside?
I understand you feel like she put you in a certain situation, but you are not obligated to go.
It sounds like his wife wants him to have friends. But it sounds like he is not good at having friendships.
You do have have to tell her you are not going because you never told her you were going.
It sounds like he has that type of personality that is one way and then changes to the other. So this would mean he could be social one day and then ignore you the next. If you do not want to be around him then do not go to the party.
You don't want to out yourself in a situation you will be uncomfortable in.
No you did not accept the invite. You just kindly said thank you. It does not mean you were going. She said she would love for you to come because she wanted you to come. I understand why you were shocked because you feel you both are not friends but just acquaintance.
You never know he might think you both are good friends.
No, not at all. You never want to go to somewhere you do not want to go.
It is more important for you to be comfortable. You do not want to go there and you do not know how he is going to react.
Then I would not go. If you do not want to be friends with him, then I wouldn't go.
If she asks why you didn't go just tell her you alreadyhad plans it was to short notice and ask how the party was.
You welcome and thank you for your questions.