Men, How The Hell Do You Have The Willpower To Pull Out?

My daughter confided in me about her marital problems. I held her and let her cry. One thing led to another and I showed her how a real make makes love. Now it's happening several times a week.

The thing is, she and her husband are trying for a baby.

I know I should pull out, but it feels so good and I'm kissing her in missionary position or she's riding me and I have my hands all over her breasts and I end up flooding her pussy with another load of daddy's semen.

She scolds me but then hops back on my dick instead of going to wash out the semen (which, though not a perfect form of birth control, would at least reduce the chances that I'll get her pregnant).

So my question to all the men here is how do you resist? How do you pull out? Let's assume you're having some kind of forbidden sex where the temptation is great...an affair, a younger girl, your adult daughter or niece or granddaughter, etc. ...