Withholding sex is clearly not the right way to go. Especially in a time of shortage.

I am a messy person and I can tell you that I am a messy person not out of malice. I am a messy person even when I live alone, so clearly I do not make messes to harm or disrespect a SO - I do not have anybody but cats living with me at the moment, and cats are not bothered by messes.

I do not have any advice, but just wanted to tell you that he does not do that out of any negative attitude towards you.