This is a pretty open ended prompt so I'm happy to adapt it if there's something you think would work better but the essential aspects of what I'd like to write with someone are this:

Your new neighbour has fast become a close friend as you discovered you both had lots of interests in common. It's not just that, though, because her marriage seems to have become boring in much the same way yours has and you've shared your dismay at this with each other over the odd glass or two (or three) of wine. The problem is your husband, lovely though he is, lost interest in you sexually a long time ago. As a result, you've found yourself daydreaming about the casual experiences you had with guys when you were younger and fantasising about reliving them again. A woman has needs and yours just aren't being met.

You wouldn't admit it to anyone but you've also found yourself visiting this neighbour's house at the times that her 23 year old son comes to visit. He's often complimented you on your dress sense and your looks in a slightly cheeky and mischievous way and you can't deny it's flattering. His mum has said it's lovely how well mannered he is but you've caught him checking you out a couple of times when she's not around and you suspect he's not as sweet as she thinks he is. When he smiles his cute smile at you it sets off powerful feelings you don't want to admit, even to yourself. A few days ago he casually touched your arm and it set your skin tingling and your mind racing with images of what you'd like to do with him. Even though your mind tells you not to feel this way, your body is telling you something very different.

Now, at your neighbour's birthday party, with your husband away on business, and both you and her son getting a little drunk together, you wonder what it would be like to act on your feelings and make your fantasies a reality.