Guys, How close is too close to a female friend?

My boyfriend has a female employee who is also a long time friend of his employed at his business. And she works mostly remotely but when she does have to come to the business in person from out of state she has been staying over our house the night before. I did not have a problem with this and do not normally find myself jealous of other women. But I noticed their body language is very flirty and they sit unnecessarily close to each other on the couch. Then one night he didn't come to bed and I came out and they were cuddled up on the couch spooning. He had drank a lot and passed out. The next day when I questioned him about it he said he was drunk and just passed out in that position and it was nothing. But it looked like cuddling and she hadn't drank anything. I told one of my female friends about this and she says I am over reacting - that it isn't a big deal. And he says I am over reacting. I felt like I had been cheated on but with everyone telling me I am over reacting I chilled about it. But now he is talking about going on a business trip where he will need her to come and they would be sharing a hotel room, because it is an expensive hotel and only one room is available. And this will probably happen from time to time in the future. How am I supposed to make peace with this and trust him? Or can I trust him? They are good friends and comfortable with sharing a room. And I don't want to be a jealous woman trying to control what he does. Am I wrong to be a little upset about the spooning on the couch? He swears he just passed out drunk and remembers nothing. That there is no attraction- nothing like that. So guys does this sound like a line of BS or am I really overreacting? And I was about to get over it but then I found out about them potentially traveling and staying together on business. How should I feel about that?
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+1 y
I have tried talking about it, but he says it was innocent and doesn't want to talk about it further than that. He seems to want me to just drop it and is annoyed when I try to talk about it. And he agreed not to cuddle or sleep in the same bed in the hotel. So I guess I just have to trust that. I am just having trouble not being angry about what happened before and wondering if they can really keep the promise to not do it again.
Guys, How close is too close to a female friend?
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