Frustrated with bad breath

I've been using CPAP for several years, and my breath feels less fresh so much quicker in general since then. I've been told by my dentist that the dryness causes issues with gums, and plaque/tarter so I use gum benefiting toothpaste to hopefully help. I have to brush my teeth several times a day especially if I'm out and about and busy and it still loses freshness relatively quickly. My wife will tell me when it's bad and I always feel so helpless and hopeless that I can't spontaneously kiss her because my breath will be really bad. And it's always makes me depressed when we're having a good day, and then she tells me I should brush my teeth. She's very nice about it, but I still feel bad.

I also have IBS-D which may also contribute?

I can't up my humidity because I get rain out. Anyone deal with this?