Is it normal that my former lesbian wife likes to watch lesbian porn

My wife and I have been married several years and she wanted to start watching lesbian porn in the bedroom many months ago. She was once in a lesbian relationship with Deidre for 8 years. Recently, she's been watching sex tapes of her and Deidre, while I'm giving her oral. She tells me what to do and won't let me stop until she has several orgasms, which may take an hour or more. She always tells me that I can have some afterwards if I do it right. She says that she gets so wet and orgasms best when she watches Deidre and her.