I am extremely nervous writing this on here, because I am worried to get everyone's responses, but that is how it works.

I have been dating my boyfriend for over 6 years now. We have a good relationship in the sense that we know what each other wants, and what NOT to do to get the other upset.
Although, in the last year our sex life has diminished to nothing. We have sex maybe once every 3 weeks. When we have it, it's great still affectionate and loving. But what I don't understand is why the both of us do not have sex more often. In January my boyfreind got a new job which has taken up all of his time. He works 8 am till whenever there's no set time, he could get home at 7-8 at night. When he gets home we eat, watch some TV together and go to sleep. I can tell us not having sex is getting to him because when I ask him if he wants to still be with me, he says I do want to be with you, but the "sex" thing is really getting to me, we don't have enough of it. He said something last night that perhaps we are not attracted to each other anymore, perhaps it is that... but what else could it be. Its like our spark is gone... and it's killing me inside.
Our sex spark... is gone. Because, when we are with people, or we do things as a couple we are still happy together, but we never take the step and make our sex life better... and I feel it is diminishing ever day.
If someone could help me, I would appreciate it please
I do still love him very much, what could it be though?

Sounds like his schedule may be playing a part, also lack of communication with each other.

You said he wants more sex, apparently so do you, so what's the problem? If you both want it, then you need to be able to communicate that to each other.

It does not sound like the sex spark is gone,it sounds like you don't MAKE time...

How hard would it be to sit in the bath together,or turn off the TV and make a start there..

You have to make the time. If you have time for TV,there's time for sex.

Those sort of hours WILL kill his libido... now is he refusing your advances or are you not making them waiting for him to do it?

Now keep in mind... he does need some decompression time when he gets home... so don't get too much in his face the instant he walks in the door.

These are all great answers and I thank you again.
I have to say, I do wait for him to do it... and of course he is tired and doesn't get around to it. I know I need to make it more fun, and I need to make a move as well. I was just more worried that maybe the spark was gone, but I do know he still loves me very much. I just cannot seem to understand the not having much sex.
Is there something that can be done, to try and get us both to get us into a great mood, instead of just routine of coming home, relaxing and going to bed?

If you have both talked about it and know what is bothering you then you should focus on it and make an effort to spice up the bedroom life. There is always some way to re-light the fire, you just have to find out what it is. I wouldn't recommend making a schedule for sex but try to find certain time that would work the best.

These are all great answers and I thank you again.
I have to say, I do wait for him to do it... and of course he is tired and doesn't get around to it. I know I need to make it more fun, and I need to make a move as well. I was just more worried that maybe the spark was gone, but I do know he still loves me very much. I just cannot seem to understand the not having much sex.
Is there something that can be done, to try and get us both to get us into a great mood, instead of just routine of coming home, relaxing and going to bed?

Like suggested above try taking a bath together or a shower and keep the TV off every once in awhile. Maybe try nice lingerie when he gets home to make him really want you.

I notice that all of your questions are concerning after work. What about on his days off or does he work every day of the week?

If he is getting no time off or very little, then it isn't any wonder that he has stress/tiredness issues.

You might try changing the routine by having sex in the morning when he shouldn't be as tired. Wake him up.

Take the pressure to perform out of the equation. Enjoy each others bodies with no intent to have intercourse. While watching TV, play around during commercial breaks.

Sex shouldn't begin only after the bedroom door is closed. You don't mention children or living arrangements that would make it difficult to explore other areas than just the bedroom.

Imagination can be a wonderful tool to use in re-building the fire.

That is correct I don't have children, we can experince sex anywhere in the house. I just feel that he is just so dead tired with his long hours that when we do have time to relax we just wind up wanting to fall asleep because we have reached the point whereby we are just exhausted. Even last night, I wanted to and tried to get him all excited, and he wanted to so much, but he has no energy. I kid you not. So I said its O.K maybe tomorrow, and I promise you, he went to bed and was snoring in 4 minutes. Sorry to bother you all, I just feel hopeless, and I worry about us.

MAKE time for your relationship, or you WILL lose it.

I find it amazing that people are willing to work overtime for a JOB, but not for the people in their lives. Yes, I know what it's like to have an exhausting schedule--I work insane hours lately, and my husband is workign on a European project, so is working overnights to be on duty when it's day in Europe--so we don't even SLEEP together.

We STILL have a date every week. Sometimes that date is cuddling on the couch, sometimes it's out for Denny's, sometimes it's just a walk around our neighborhood. The point is that at least once a week, we MAKE time for each other.

Since we started date night, it's very seldom that one of us is complaining about lack of sex in our relationship, and that usually is because of 60-80 hour work weeks, not lack of trying.

I'm sure your boyfriend isn't working 7 day work weeks. Reserve 4 hours of his time off as your "date" time, and start re-connecting mentally and emotionally from there.

You aren't bothering us. You have concerns and are asking for ideas. We'll give as many as we can and hope that something works.

A lot of your current problems sound like timing and tiredness and it is turning into a stress on the relationship.

Does he have any days off work?

Have you tried having sex in the morning instead of at night?

Tiredness can be an absolute passion killer - believe me, I know.

Part of the problem, as I see it, is that you're expecting everything to be spontaneous and like it was in the early days. You're also expecting there to be a simple solution. Not having sex is a habit, and like any other habit - it can be hard to break. You have to be aware of it and be conscious that it needs to change.

So, you have to make the effort - if after work doesn't work (and clearly it doesn't) - then change the time. Why keep flogging a dead horse? Talk about it and make it fun - make a 'date' as others have suggested for the weekend. It does take the spontaneity out of the equation, but remember, you're trying to break the habit of not having sex.

It's really easy to just flop on the couch and bemoan how tired you both are, but this is the test of any good relationship - to do well when things are challenging.