Do I do subtle?

I've been reading this book called Conditions of Faith by Alex Miller. I'm quite liking it but my urge to slap someone around the head is become difficult to control. About a quarter of the way through the book, the main character, the newly married Emily, discovers that she is pregnant. I'm ok with that, but then she gets worried that the baby isn't her husbands.

Ok ... so what did I miss? Turning back the pages I come to a meeting that Emily has with a priest whilst taking a tour of the church. She gets lost from the group, yada yada yada, is found sitting lost and alone by the priest. They talk for a bit, and then the priest escorts Emily back up to where her husband is waiting. Let me quote -

'It's no good,' she said hopelessly. 'I must get back!' He was looking up into her face, his neck thick and powerfully muscled. She reached and with the tips of her fingers she touched the vein in his neck and felt his heartbeat surge beneath her fingers.

And that's it. So, from this, I am meant to know that she shagged the priest in the bowels of the church only five minutes after meeting him. Honestly, at least give us a hint. This is what I call a Tess of the D'Urbervilles moment.

Maybe the problem is that I just don't do subtle.