You both probably let things slide for too long without checking in with each other. I would say your relationship is in a state of emergency and it needs emergency treatment. Is there any way you can get off work for a few days and take her away somewhere, just the two of you? You need to reconnect with each other quickly and a little trip away from the usual routine might help get you back on track.
Once you get some positive feelings flowing again from showering her with romantic overtures, you can start talking about what happened and figure out where to go from here. Maybe you have to specifically plan how you're going to stay connected with each other emotionally. Do you really need to work 7 days a week just to pay your basic bills, or are you doing this so you can have extra money? If it's at all possible financially to cut back your work hours without taking too much of a hit, I would do it if I were you, so you can spend more time together.
You don't say if she is working long hours too, but if she's sitting home on weekends while you're at work, that's very depressing for her and it makes her wonder how she got herself in this situation. I know that life sometimes isn't perfect and we just have to do the best we can with what we have when work and love don't mix. But it must be possible to still maintain a relationship under trying circumstances. I think when times are tough, couples have to bend more to maintain that close connection. I know that it's easier said than done to balance work and love, but as you said, it's worth it.
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