Adding some pressure is where the email comes in. Not sure it will help, but it does get things out and at least the topic is broached. She replied already, and as is usually the case angry that I brought the subject up and blaming child care duties as the cause.
These days, both kids are in school all day and she is a SAHM. Rather than taking a well deserved break, she is busier than ever, which according to her is why she is too tired. We take turns cooking dinner, I do a lot of the house work, and give S5 a bath and book/bed every night. I don't believe the average woman would consider this an overwhelming responsibility. I don't drink, smoke,gamble, don't beat my wife, make well into 6 figures, house paid off,etc.