MrB, I think that the problem is that people misinterpret what a lack of respect really means. For instance, your EX having to come to you every time she wanted to make a purchase built up a lack of respect towards you. You may think it was resentment, but I think the two really go hand in hand.
I know in my own sitch, after I took control of our finances back many many years ago (my W had setup auto payments on things resulting in a negative checking account and huge credits with a few of our billers), we ended up with a very similar dynamic as yours. My W would suggest we should get something, I would say yeay or nay. Over time this dynamic created a daddy-daughter relationship between my W and I. After Ring and piecing we went to a budget system. We allow so much for clothes, household items, etc. So much so that my W now feels comfortable making fairly large purchases without my thumbs up. She a couple of months back bought a fairly expensive floor cleaner without more than a mention that she had ordered it to me.
The control side of my still freaks out a little inside about this, but the last thing I want to go back to was that daddy-daughter dynamic we had between us before. So I allow her the leeway, within reason, to buy and order what she would like. I find it interesting that the less I worry about every penny of spending, the more discretionary spending money we have!
Back to the point, resentment to me leads to a lack of respect. And sometimes the WAS/WS doesn't even realize it themselves! My W on BD and shortly after it continued to say she had the utmost respect for me, especially as a provider and a wise finance guidance counselor. Yet her behavior was saying that she had no respect for me, largely because of resentments that had built up over time. So it isn't that they are separate as in either lack of respect or resentment can lead to a WS. I think the resentments build up to cause a lack of respect. Now that doesn't mean that is the case in every situation. Other things can cause a lack of respect, like be a beta male in the relationship, etc.
M(51), W(52),D(16) M-20, T-23 Bomb Drop - Dec.23, 2017 Ring and Piecing since March 2018