Why do older men become bisexual?

I have been wondering about this, as many of the men on here indicate they are experimenting or wonder what it would be like to play with a male. I started several years ago after my wife went through menopause and did not have any interest in sex. Our sex life slowed down a lot and wasn't as adventerous as before, even though I used lots of lube, massage, oral and foreplay. I kept myself in shape and still weight 175lbs at 6'1". I even encouraged her to take a lover if that would help, but no interest.

I decided to see what a male touch would be like. Living in a warm area where we have nude beaches made this easier. I have played with a couple of men, but their wives were there, so it was fun being with a couple and satisfying. However, this is not something I would have entertained if I was enjoying my spouse.

Therefore,the question. Are other men and women placed in similar situations and why? As a couple we brought a couple of men she thought were hot into our lives, and I always enjoyed her being with me another man. Very sexy and she always picked the guy out, so it was her choice. Share your thought and experiences.