I think My brothers wife likes my husband

So I’ve known my brothers wife about 6 years now. She came in pretty abrupt since he was engaged months before and then she just announced they’d be marrying. So my family was a little throwed but we love my brother so we were supportive. Since entering my family she accused my parents of being narcs, caused so many arguments , cursed out my dad and my brother did too which is out of character for him. On my wedding day she insisted she did her own makeup and myself and other bridesmaids were waiting on her ( I included her in my wedding and it was the first time I met her in person). When she met my husband she is always complimenting how attractive he is, my brother and I ignored it because we thought it was her being playful. I remember my mom pulling me to the side that day though and telling me to watch that girl because of how much she kept saying it. I just responded I know but it seemed innocent. When her and my brother would fight she’d call me for advice and I’d give her, since we are young and married we leaned on eachother. One day recently, when my husband I argued I called my brother for advice and she called my husband to check on him instead of me ,which for some reason made me uncomfortable. Like why did you call him and give my opinion on it to him. Then a few days ago he picked me up from work and she called him , he put it on speaker because he didn’t want me to think anything and when he said hello ,I was going to greet her but she had this really girly flirty voice on that I never heard before and she told him “he’s so comforting”, he looked surprised. So I was pissed, I went in the house because I felt conflicted about it being a personal convo. When I returned he was off the phone and he told me I was right it seemed she liked him it felt weird and he feels bad for my brother. I told him that we should give them space and stop being around them we agreed. Last night my brother called and we were talking she was in car silently, I told him I was watching a show he brought up and he was like really? What a coincidence and he told her like “babe guess what she’s watching” . This girl responds that the main character (who is a really attractive guy but looks nothing like my husband ) —looks like my husband. Just randomly no one brought up my husband at all so my brother laughs and said no he doesn’t , she thinks everyone looks like your husband. I just nothing and when we got off phone I told my husband and he was like I was right all along let’s keep our distance. I got an answer but I feel like I’m tripping or something and like this can’t be. I’m a big sister and he’s like my closest friend. Am I just insecure?