Posting here for traffic. DD 17 and I have a very close and what I thought was an open relationship and communicate well. She’s recently switched sixth form and started mixing with more boys which is to be expected and completely normal. She’s become very close to one boy, who I have met and given lifts to and from social gatherings etc. I did ask her if it was more than a friendship and she’s always maintained they are best friends only. Its half term this week and I found out by chance that she’s had him round in the house whilst we have been at work without our knowledge and stayed for over two hours. I know this because neighbour asked me to check my cctv for a delivery which was supposed to have been made and wanted to know what time it was made(separate story) so hence why I was checking footage. Anyway, DD hasn’t told me he came over, and has been behaving quite furtively lately. I had asked her earlier what she did that afternoon and she said she was just watched films on her own so clearly didn’t share that he was here. To me that implies something fishy and perhaps al little fooling around going on?
I feel my trust has been broken; do I tell her I know that he was here and ask why she didn’t share with me? Or do I just make out I don’t know but keep close eye? Advice needed as I don't know what to do..