Makeover time and sex scenes

Since we've had two days of sunshine here, and the bulbs are all flowering, I thought it was time for a cheery change of scenery. The husband and kids are ripping up three layers of carpet in what will be the 'guest room' and the wreckage of yesterday has been transformed into a neat patchwork of plasterboard, ready for finishing.

Meanwhile, I'm wrestling with the sex scene. Or rather, the nearly sex scene. How does anyone write the bloody things? I'm acutely conscious that at some point people I know or worse *gulp* parents might read one. It seems strange to me that you write a scene of violence and no-one thinks you're a blood-thirsty psychopath but the first hint of sex and they assume it was a) completely autobiographical and b) think they know who the other participant was. A few even think I'm writing about them.
It's like poetry. I wrote a poem about seeing my sister after she died. I used a bit of poetic licence - surely designed for that very purpose - and brought in a  few details of a previous occasion when I had viewed the body of a loved one (I went through a really bad patch). There has been debate about 'what actually happened' - which is ludicrous. I want to hide a bit behind fictionalising the account, doesn't everyone?

Fortunately, since they don't actually have sex, it's a bit easier to write.  At least I don't have to explain what went where (like the reader doesn't know that already). But - and I am not shy about sex - at least I don't have to go into any detail. I think my readers are bright enough to have already created the protagonists from the story and can conjugate them however they want.