Hey ... how old are you?
Look man, I used to go visit my aunt every morning when I was 17 on the way to school. She was an old lady and I had no attraction for her whatsoever - but, I don't know - time of the morning or whatever - I would have to hide my boner when I got up to leave her house. It just happens that way when you are 17.
Not so when you get older. You don't always just "pop" to attention at the sight of a naked girl.
Also - someone posted above that you "lose" attraction to your wife after a period of time. Well, I have been married for 25 years and I'd charge through a platoon of 300 lb Samoan wrestlers if I knew my wife was on the other side of them wanting to have sex with me. In fact, sometimes I take off work on Fridays at lunch and me and the old lady will hit it for hours.
We have sex twice a week - she's 52 and I'm almost 50. She is still hot as hell to me. You could put her in a lineup with the finest looking girls in the nation - and even if she told me it was okay to pick someone else - I'd still pick her. Now - if she weren't in that lineup then I'd pick Kirsten Bell - damn me for the bad luck! LOL!
If you are sexually compatible - you can stay attracted forever. My wife is sexually submissive and I'm sexually dominant - so it works. A lot of guys get pissed off that their old ladies don't initiate sex but not me. My wife tells me all the time ... "I wasn't in the mood when you started, but I damn sure am now!"
It helps some to have a wife who's open to doing different things to keep it from getting boring. Wives that have the word "no" in their vocabulary suck.
People take sex too seriously - just do it.
As far as erections go - mine usually come and go. When do you really need an erection bro? Think about that, I'm not going to get too graphic on that - but there is only ONE time that you need it. You don't need one when you are sitting there in bed discussing the grocery bill with the old lady. That's usually what happens with older men - it's there when you need it. When there's no stimulation - it goes away - but it always comes back when the stimulation resumes.
Another thing is ... when you are older - you don't need sex as much. In fact - I don't think you need that much when you are young either. I once had a girlfriend when I was in my early 20's - and we hit it everyday, about twice a day. But - I would go out to sea on my submarine ... like sometimes for a week or two - and the sex was ALWAYS ALWAYS hotter after I had been away from her for a week or so. I was always more satisfying and memorable. I used to wish that I had the willpower to keep away from her and only have sex once or twice a week but I didn't have that kind of willpower when I was younger - and had to have it everyday.
So twice a week is awesome for me and my wife - and we get really DIRTY when we do it. And she's willing to "go there" because it's not something she has to deal with everyday.