Crazy other woman

My husband and I have been together almost 20 years. I love him and I’m not worried about infidelity he treats me like a princess. Before we got together he went out with a woman who he denied being with because he was embarrassed, she now works in the building where my husband and I work. She has told people we work with in detail about being with him, where at how many times, his size. She’s really mental but now every time I see her I picture this in my head, it’s driving me crazy. My husband doesn’t know how bad I’m obsessing over this. He denies this saying she chased him but he didn’t have anything to do with her. I think he’s lying. I’m not jealous of this woman, just embarrassed that she’s said all this stuff about my husband to our coworkers. Now I picture them together. Am I going crazy?

simple go to her, tell her to shut her mouth and move on with her life, if your husband said no he never slept with her, who are you going to believe the crazy lady or your husband who you have known for 20yrs