‘After 10 Years Of Marriage, My Wife Doesn’t Like Sex Anymore’ – Worried Man Speaks

According to a worried man online:-

I have been married for 10 years and we have 3 wonderful kids. She took a well paying but stressful job recently and her sex drive has reduced drastically. We now have sex like just 4 times in a month.

She doesn’t ask and if i ask it is always excuse of fatigue.

She doesn’t cheat, i am 100% sure of that.
She even told me she wont mind if i find another girl to satisfy my urge.

I am not the type that can cheat too.
So I am worried on what could cause this change. Someone told me it could be an infection