If your partner is working and seeing clients every day, it is highly likely that as MrLittle said, she needs a break. Even if she was not a Working Lady, any woman, well most anyway would soon get tired of having sex multiple times every day (yes i know thier are exceptions) and then having sex one last time with probably little patience by then would make a saintly woman snappy, irritable and grumpy when all she wants is a hug and intamacy, not more of the same.
My suggestion is that you ask her to have a chat over a drink when she has rested, tell her that you realise that what she does is draining, that you love her and want her to be happy. If finances allow, ask her if one night a week you spend time together just relaxing and enjoying some time with a hug or two. You will have to let her know that you realise she will also need her own space to relax. If you can achieve a dialogue and bear in mind you will have to take time from.wanting sex you might just become a more relaxed couple who can enjoy each others company and continue together a lot happier.
If as time goes by, she becomes more relaxed and feeling more at ease without pressure from the one who is her partner, her one to come home to, suggest that you would appreciate her telling you how and what makes her happy, what turns her on so that you can be a better partner, a better lover and you both will be a lot less stressed.
I hope that things work out for you and your partner, take it easy and try to be patient and as understanding as you can.