JohnQuig You really are very immature and argumentative.
Nobody is saying you can't choose not to have involvement in certain parts of a game. But a 12 year old child shouldn't really have to chose his own content throughout the game, they will not know what they should/shouldn't be censoring for themselves. And it is not just about the sex. I wouldn't want a 12 yr old of mine getting entertainment out of any of the main 3 characters of GTA, and I wouldn't expect them to understand a lot of what's going on either, and I wouldn't want their questions about certain subjects be based on a game.
I'd rather that my children were older, and well aware of the situations a certain game and film are portraying, before they go and experience them or play them for entertainment.
When you have you're own children you can do what you will with them and let them see whatever content you deem fit.
The OP asked if she was being unreasonable to not let him play certain 18 rated games that his other friends play, but maybe let him play some 16 games where she deems the content ok. She is not being unreasonable, she is sensible and looking into the content of each game individually.
You banging on about what you were allowed to look at and what you would let people look at and what you think of other people's parenting is just ridiculous. Yes your parents let you do what you want in that sense, so did mine, doesn't mean I will follow suite, I actually think my parents were quite naive in what they let me do, so I'll probably be a bit more strict and aware than they were.