Went to dinner with CA friends, relatives from out of state, sat next to 'friends' wife, and found her hand on my thigh! What to think?

We had probably 10 people at the table in nice south county restaurant. Next door neighbor and wife, long term younger married couple I had know since moving to CA, two cousins and their husbands. Sitting next to me was the wife of a married couple I knew for many moons and socialized with for several years, drank, smoked some pot etc. During the meal, I found her hand on my right thigh, and almost choked on my wine.

My thought... I don't need this kind of complication, or trouble, in my life at this point" I ignored the hand and it was soon taken away. I later thought that it was 'innocent', although something like that is usually intentional. I think most single men would have went forward with it and did whatever would happen, but at that point in my life (a year ago) I simply did not want to get involved in something with a friend's wife that could ultimately turn very ugly... i. e. The husband was a heavy drinker, and kept guns in the house, BUT did make long motor cycle trips out of California on some weekends.

Thoughts on how prudent my decision was / or NOT!

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This question should be under "relationships' or 'sexuality' I don't know which
Went to dinner with CA friends, relatives from out of state, sat next to 'friends' wife, and found her hand on my thigh! What to think?
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