I feel like it would help you if you paid attention to the part where you sound like you're angry. I understand you don't mean them but then for us stutterers, that's how we speak and it's also valid for your wife to feel that way sometimes. Whenever you're talking, if you feel like you're gonna have to push a word out which might entail it sounding a bit rough, you can try modulating your voice a little. That helps me. You can stretch the word a bit and instead of pushing it out, you can slide it out, if you know what I mean. But again, i don't think i am in no position to advice you because i struggle with tone myself (because i also can't catch on social cues bc I'm neurodivergent) but I'm also working on it. I hope what I suggested helps you. I'm really glad you have a partner who is so understanding. You're doing really well, too. I think a bit attention and practice will help you a lot! Hope you have a good day!