[50F], [48F] - Partner is very sensitive and takes everything personally.

Can someone please explain why my partner takes everything so personally and what I can do about it? Today she was upset because I asked if she had checked the dogs' paws for dirt before they came into the living room. We live in the countryside, and after dog walks can get quite messy, so they usually stay in the conservatory until they dry off. I simply asked, "Did you check her paws?" I meant no harm; I only wanted to be sure since I know she sometimes forgets. The other day, she got emotional because the decorator used a colored caulk that I thought looked nice against the stained wood, but she disliked it. When I continued the conversation and mentioned how it concealed the previous messy paint job, she interpreted it as me disagreeing with her and ended up in tears. I was sharing my perspective, not trying to hurt her feelings. She seems to cry frequently and often blames me for her emotions. On another occasion, during a three-way conversation with her son, I was mostly listening. When her son asked for my input, I expressed that I didn’t want to get involved, as I didn't want her to feel cornered. She dramatically leaned back and exclaimed, "Oh my God, I feel ganged up on!" I recognize her sensitivity and genuinely want to support her, but it's frustrating when she attributes her feelings to me. I’m not claiming to be perfect, but I should be able to express my opinions without her getting upset. For context, my disagreements with others don’t usually lead to such strong reactions; they can handle differing views. She, however, tends to cry and become distressed around many people. How can I help her understand that her feelings and reactions are her own? I’m always willing to assist, but it's not fair for me to bear the blame for her tears or assumptions that I’m against her. I can’t be expected to take responsibility all the time, even though I often do. Any advice would be appreciated.