Believe it or not... I think you are bored. I know you have lots and lots of balls in the air, and you do lots and lots of stuff... but I don't see/hear about anything that really 'stimulates' you... other than sex. And I'm not trying to be funny when I say that either.
Sex IS stimulating... the connection you get with your partner IS stimulating...
even arguing with your H over not getting sex is stimulating. I don't know that it's the kind of stimulation you want or prefer... but, it still is.
I don't see that you have anything in your life that is challenging YOU.. Loon, her, the one inside... that very smart cookie who's mind travels at warp speed.
