For context and balance, I really don't like my cousin. She is unhappily married. When we have large family gatherings she will never bring her husband. At a recent event, she flirted and told one of my friends that she was single. When word got around, everyone thought it was funny, typical 'her' behaviour, it's okay they were just having fun...
My husband gets on with her well. They message each other on snapchat and have done so for a few years. He has on occasion mentioned that she has messaged something about family matters. I've never really taken too much notice.
My cousin and family came over to stay for two weeks. My husband is jovial and so is my cousin. At an event they spent most of the day chasing each other, play fighting with each other. I felt uncomfortable, it reminded me how we behaved when we first got to know each other. I didn't say a word, perhaps my feelings are wrong. Everyone else seemed to find it funny. Their behaviour continued across several different events. My feelings became more uncomfortable but I didn't say a word, I mean he is my husband and she is my cousin - surely they understand where the line is.
My mom recognized I was unhappy, so she decided to have a word with him about how they are behaving without telling me. He came to me afterwards saying that he was sorry and didn't feel that anything was wrong, he saw her like a sister and wouldn't do anything to jeopardize our relationship and family.
They have stopped the play fighting, but I noticed that both of them are constantly on their phones. My husband received a message from her and whilst replying realized I was walking right behind him. He quickly changed the app to another one and lied saying that he was replying to another message. We were all in the same room when it happened, they could have easily spoken to each other.
I feel bad, but I couldn't help myself, I looked at his phone and discovered that they are each others no1 messaged friend on snapchat for the last two weeks (the same time frame that we have all been together!). Furthermore, she has sent pictures of herself posing and he has saved those snaps. None of the pictures are explicit or flirty. My husband is constantly on snapchat, if they both are each others no1 messaged friend, I don't understand how there were very few messages in the chat - unless he has been deleting them, if so why?
I feel like I'm messy at the minute with a lot to lose if my actions are wrong. Is it reasonable to speak to my husband about it or am I just being unreasonable about their friendship. I fear that my family will side over to her and I will become the outcast.