32 year old boyfriend intimate with 60 year old ? ?

My boyfriend of 4 mths has only been intimate with older women around 40-60 years old. When we first started dating he mentioned how he met this 60 year old woman and was feeling very lonely . He said he didn’t like her for her looks but for her personality and they only hugged and kissed. He told me he would never be in touch with any women he has slept with while with me but asked if I was ok with him checking in on her as she is very unwell and he was worried about her. She has had a very hard life , suspects she has ms and her daughter stopped taking to her, her husband abused her and her daughter. He asked me at the time if I was ok while we began dating if he checked in as he worries about her. I didn’t think much of it at the time and said yes as I felt sad for her. He didn’t even want to show me a picture of her as he said that he didn’t go for her for her looks. He told me he spoke to her recently and he told her about us and she wished us congratulations . He asked me if I’m ok with him talking to her once every few months , if not rarely. He wanted to sleep with her she didn’t allow it. He wants to marry me and I’m in love with him and he says he is in love with me. I said I was ok with them talking but it made me uncomfortable hearing about it and he said he would completely understand if I said I wasn’t ok with it and would stop. I said I was fine with it. It wasn’t a relationship . Is it ok to be ok with it even though it makes me feel slightly uncomfortable ?