I don't like the same meal too many times in a row, but I don't mind cycling through just a few dishes in one week.
I'll make 3-4 different meals and DH and I will cycle through them, so we're never eating the same dish two meals in a row.
I have over 100 vegetarian recipes that I cycle through, so I might have one dish a few times in a week, but I'll probably only cook it a few times a year.
I didn't just decide to cook this way, it's just how it ended up working out to fit our lifestyle best. Don't worry too much about coming up with a preset plan, focus more on figuring out what you want to improve on and customize your own routine from there.
My best advice is to either cook or buy some easily heated meals that can be kept in the freezer. This can really help when building a new meal planning strategy.
It should be noted though that the frequency of your shopping doesn't actually have anything to do with food waste. If you start planning properly, then you could shop every single day and still waste virtually nothing.
If you think this is the best way to approach the challenge, then great, but I see you tackling two separate issues at once, and I personally tend to find that sets me up quite a bit more for failure.
You have the issue of over buying and under planning your cooking, but then you also have the habit of shopping as a therapeutic measure.
Personally, I would put my energy more into the meal planning side and not worry so much about the limiting shopping trips side, because that's the more complex issue.
If your ideal meal plan has you shopping for fresh produce twice a week, then that's perfectly reasonable. Also, if you are meal planning effectively, that will basically eliminate grocery shopping as a self soothing option, because other than on planned shopping trips, you won't have any need to go to the store, so you will still have to come up with better options for getting out of the house.
Two birds with one stone sounds good in theory, but what you have are two separate issues that are probably best tackled through two separate approaches where if one fails at any moment, it doesn't take down the other.