Strip Clubs but no sex

I don't understand this; hoping someone will have some ideas about this.  My DH is ADD I am not. DH is not treating ADD at all and hasn't for over a year. DH is also bipolar (1 yr since begin treatment) - he is treating with meds only.  Okay, so that's the back history.  For about the last 3 + months my DH has had no interest in sex- none. He's too tired - no energy whatsoever. Okay fine. DH also has within into hisself and has limited (at best) contact and conversation with me (he leaves the room when I enter, stays up late surfing the net to wait for me fall asleep, ect) Okay, I just have let him have his peace no pressure from me just go on with life as is. 

About 6-9 months ago I found a business card from a local strip club - felt strange about it but decided to trust DH and not my gut instinct - I tossed the card and didn't mention it.  There has been one other "clue" that I just passed off as men doing what they need to do apparently.  Anyway, this morning his wallet was lying open on the counter - my gut told me to look inside.  Yep, another business card from a strip joint (a different one from the first).

Aside from feeling like I've been blindsided (again) - I can't seem to process this. Is this an ADD thing?  The whole implusivity (which he struggles with so badly) thing or ???  

If I were to ask him about it he'd lie (not his, he doesn't even LIKE going to strip clubs, ect ect)

All suggestions are appreciated.

PS - Not sure if it matters or not - but sex for him is not a priority or a "need". Is this a cope out or are the strippers enough glitter and shine to hold his attention to get enjoyment for himself?