OP, I think I have a fairly good sex drive, and I wouldn't be happy if my relationship with my DH meant no sex. However, I would be completely devastated by a lack of any physical intimacy or affection, which sounds like the situation you are in. It is the little touches/hugs etc that really cement our relationship. I am not surprised you are struggling with this.
Clearly you are both working massively long hours in stressful situations- you at a new business and DW at home. I don't discount the amount of effort and energy either of you are having to put in, and I think something has to change on this front. Namely you both might have to compromise and cut down the amount of hours you are working even if it means less money coming in or paying for more help.
Basically it sounds like you really miss your wife, and I wonder if you could just tell her that? Not I miss sex etc but that you miss her?
Possibly I'm being naive but I think the sex issue is something that could be worked on in the context of an intimate and affectionate relationship but I think that has to be regained first.
A word of warning: you said in an earlier post
" But, as somebody said to me recently, sex is important and celibacy is not an option for me, no matter how selfish a conceit"
Who was it who said this to you??
Not by any chance one of those attractive work colleagues you have been fantasising about, was it?
Be very, very careful. Anyone who is not supporting you in getting your relationship with your wife back on track is a snake in the grass and should not be tolerated in your life. Even if they appear to be a friend. Get rid of their influence.
I believe you when you say you love your wife, and if you wouldn't have that conversation in the same way if you knew your wife was listening, you shouldn't be having it. 'The nice woman at work who understands how hard it is for me to be celibate so is comforting me' would be an easy trap to fall into. Don't do it to yourself!