Contact or no contact

I am a 50 years old man. I have been very good friend with a woman my age. While we had sex one time she now wants to be only friend. We do not talk to each other anymore without any clear reasons. We were supposed to go on vacations together. I invited her and was paying for the hotel. We went together last year in the same place and we had both a good time. Last month, she told me that she was not sure to come. I told her that I need an answer by the following day. She got mad and told me that in this case she was not coming. She even did not mention why she may not be coming. Since that day we did not communicate at all. I am upset because I like her and I miss her. I have been always very kind to her but I think that she has a tendency not to reciprocate. To make a long story short, I think she treats me often like crap. She keeps telling me that she cannot “deal with that” as soon as I voice a concern. I am upset because I do have only one more very friend beside her. She always wants to spend the weekend alone and reject often my proposal to hang around. I am aware that I cannot control the behavior of others and cannot force anyone to hang out with or talk to me. I can only control how I react to the situation and how to respond to it. I am waiting for her to contact me but I think that she won’t. I do not want to call her since I did not do anything wrong and since I am always the one to initiate communication. Should I move on and forget her which means to be even lonelier? Thanks if you have any input.