I see your point. What I want to say is that nobody wakes up one day and says: I will have an affair. Or maybe some do. I don't know. What I know is my own experience which stemmed from years and years of trying it all. Getting therapy, communicating needs, humiliating myself for affection, putting my needs behind, not prioritizing me in any way, always being there for my family and generally being the "good girl". Many good girls, hear me, are sad. I have never been this happy in my whole life. I'm not morally clean but honestly I don't want to die with the regret of not experiencing romance, passion, intimacy. So, yes. It's a selfish act. I understand the consequences and in my risk analysis they're worth taking.