Female Employee is eating meals alone with husband and is avoiding me. Treats me coldly, is super sweet to husband.

TLDR below
My (M55) husband and I (F55) have been married 29 years. We own a business that is run by a manager (F58) who lives nearby and has been with us 2 years. As owners of this business my husband and I are on site together and sometimes my husband is there alone and sometimes I am there alone. This business is five hours away from where we live, it is hospitality, so we have to be there during high season to help out but not always. I usually stay home to take care of our kids, while my husband commutes back and forth.
Our manager (I?ll call her Sue) is great at her job and we both get along with her well. It?s a very professional relationship. Sue is single.
My husband and I usually make our own meals and eat on site in the employee kitchen. It is the only kitchen on site. A lot of times our manager is there when I am cooking food, and I invite her to eat with us, as I make plenty. For the past year, she has been happy to do this. It also gives us a chance to talk to her about the business, then we get a lot of work done over dinner. This happens maybe 3-4 times a month. Also, this past year we?ve gotten to know her really well and she loves food and is not picky with food. Whenever we go out to eat and have leftovers we offer her the food and she enjoys getting food from us anytime.
Lately, I have noticed a difference in Sue. She seems cold to me but not my husband. I thought maybe I was imagining it but 3 months ago I was making food and invited her to eat with us. She declined, saying she did not want to eat all of our food and that she had brought her lunch and she preferred to eat on the go while working. I told her no problem and that was that. I asked her again, when we ordered pizza a day later, it?s her favorite and she declined. Oh well. No problem. A couple of days later I tried to include her and she declined, saying she wasn?t hungry.
A month ago, my husband was working a week long stint alone. He calls me and says he and Sue ate take out BBQ for lunch together. Ok. Then a couple of days later, he sends me a picture of a plate of food and a yummy dessert that she cooked and brought him from home. Also he cooked stuffed pepper I left him and made one for her. She ate it. And now a week later she brings cake for my husbands birthday. I asked her if she would like a burger with us. She says no.
I worked alone a week with her and invited her to enjoy some BBQ. She declined. All week, she declined.I confronted her and asked why she feels comfortable eating with my husband only and not me. She claims nothing is wrong but won?t look me in the eyes. Now she is cold and avoids me. It just feels weird. Help.
TLDR: Manager only eats with husband and brings him food and is acting weird towards me.


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