Is there something going on with my husband and his colleague?

I have been married for 14 years (we are both 44) and we have two children together. My husband has worked at his company for 12 years and a new woman started 8 months ago. Since she started, he brings her up all the time in conversation. He thinks she is great, funny, smart and always seems to bring the conversation back to her. They work closely together in a team of 2. The wider team is only 9 people. They both go to meetings a lot just the two of them and recently they went to a works do away for the night. The two bosses went too but he drove just the two of them up there. He wasn’t originally going and then on the Tuesday he came home to tell me he was going on the Thursday. He went to get a new shirt as it was an event in the day but black tie in the evening. He did call me on the way there (on speaker in the car with her there) when he was getting ready for the black tie event, and also on the drive back (with her in the car again). He doesn’t seem that different but should I be worried? We don’t have sex much although I did have sex with him on Tuesday when I knew he was going. I have looked her up and she is gorgeous. Completely his type looks wise and she has an amazing body and big boobs. I don’t know what to think. Do you think there is something going on?
Is there something going on with my husband and his colleague?
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