Hi Brenda!
I can't speak as one taking the medications you are, but I'd like to encourage you as someone who has been dealing with chronic pain now for the past two years.
I think that *ANYONE* who is dealing with illness and pain, has days and stretches of days when they just feel sad, angry, frustrated and anxious. It is sooooo NOT the way we chose our lives to be. It's not the way we envisioned them or the way we planned on them going! We didn't get to choose if we wanted to be in pain, or take medications that changed our mood, or made our skin feel like it was on fire, or prickle like it had ants under it sometimes! We certainly didn't choose to have to stare at our four walls of our home all day, when we'd rather be outside gardening, or swimming, or at a movie! We didn't get a say in having to be strong all the time, even when what we *really* WANT to do is run home to our own moms and dads and bury our faces in their chests and cry for a week!
But what we actually do is put our feet on the floor every morning, take our medication, and strive to LIVE another day! FIGHT another day! SMILE through another day! And let''s face it, some days? That's hard. Some days? You'd really rather just kick a random stranger in the shins. So, yes, we get grumpy. We get mad. We cry. We whine. We mumble and grumble our way through and we find a way to survive. And, YES, sometimes that means it comes out in one big messy gush, with the person that we love and trust the very MOST -- our spouses.
Maybe there's a way to find the words to let your honey know some of this. Heck, let him read it if it helps!

On the really bad days, a grumpy attitude with him can sometimes be the HIGHEST expression of your love for him. It means that when you are at your lowest and most vulnerable place. He is your Go-To. He's your rock.
Of course, you could always get the marshmallow shooter guns and shoot marshmallows at each other.

add a little levity to the otherwise really crappy moments right now.
Just know that you're going to be fine. As long as you can continue to vent all of this stuff out, and as long as he can hold you up and your LOVE binds you together, there's nothing you can't do. Cancer doesn't even stand a chance against a love like that!!
Take care and have a pain free and blessed moment today.
Love!