Does the soul ever move on after a breakup?

I (23f) split from my 3 year long relationship from my ex (23m) 6 months ago. We share a child, and we’re on the “I can be in the same room as you but I can’t stand you” level because of the way things are unfolding with custody.

However, he got into a new relationship within a week of us splitting-with a girl he had been speaking to for months prior to the breakup. I have remained single and focused on getting my life back together for our son-which I have 90% of the time. I am finally in a place in which I’m ready to put myself back out into the dating world. At least, that’s what I thought. I can’t speak to a guy without thinking about the way he used to talk to me, and I can’t thinking about being physical with another man without thinking of him and how it was between us when we were physical. It’s like my brain has moved on but something in me still longs for him. My heart knows I deserve to be happy, too, but I can’t seem to get over it.

Does that feeling ever go away? Can I ever think about being with another man, or even speak to them, without thinking of him?