TTC turn on?

I've always heard men can start to hate sex when you start trying to have a baby. I guess it's because it can become stressful and feel like a chore after a while. But it seems my husband has become almost infatuated with me since we started. Grabbing, kissing, being handsy. Even when I'm not close to ovulating, he pretty much downs me. This morning before I even fully woke up he was kissing and snuggling lol I'm not complaining though. So far I've enjoyed all the attention. But he has told me just the idea of trying to have a baby gets him going. Do you think it's a primal type thing that has to do with our hormones? Pheromones, testosterone, etc? Is it just the baby making process? Anyone else's loved one like this? Did they stay this way or did it eventually change?