How do I support my partner better? I’m in a fix.

How do I support my partner better? I’m in a fix. I (32F) struggle with sensitivity to hormone changes in my body. I’m religiously taking therapy, take medication to deal with my symptoms, and do everything I can to improve the situation at my end. Once a month, I feel intense anger as one of the symptoms of changing hormones. Some anger comes from my deeply traumatic past (which again, I’m working on resolving sincerely). I become protective of myself in romantic relationships because I’ve been processing one my parent’s infidelity. The problem is that my partner(30M) of 1 year told me last night that his stuttering is now worse than it has been in years and I felt guilty and hurt. It feels like I’m directly responsible for his struggles to say simple words and it makes me feel awful. Can someone explain to me what’s happening here? I’m feeling a bit shell shocked. Can partners have this affect? I can see clearly that I need to learn to communicate better when I’m upset. I feel rather small at the moment. I don’t want my partner to suffer. I don’t even know if he is right to directly connect his stuttering to my own struggles. He has been in other stressful situations too in the past months, but he linked him getting worse to me. Edit: I understand that this group is unaware of what my medical diagnosis is (PMDD). So some of the things I’m hearing I’m not gonna take it to heart. Please know that just like most of you in this wonderful group don’t chose your condition, it’s the same with PMDD and it’s symptoms. Anger is an emotional symptom, not who I am 99% of the time. I’m just trying to understand the role and connection of stress with stuttering in a relationship setting and what can we both do as a team to have better communication during conflicts. I feel my partner’s response to general stress/ self confidence isn’t something I can contribute to unless he works on it himself, the same way handling my anger is on me.