I think my son’s father is stalking me or has bugged my home. Please help me figure out how.

Hi everyone. My son’s dad and I were together for 10 years. Unfortunately the relationship came crashing down a year ago. We own a house together and he packed up his stuff and left. The fallout has been pretty nasty and we argue every day. We have both retained lawyers to fight for custody of my son.
We weren’t legally married so we need to figure out the housing situation afterwards.

The problem I’m having is that today I realized he is stalking me. The last time he and I were intimate was 2 years ago. So naturally, as a 36 yr old woman I have needs. I slept with a new friend who lives on the other side of the US a couple of months ago. Somehow, my ex knows that I slept with this person, what his name is, where he’s from, what his profession is, etc. He has brought up very specific things that I have said in conversations with this friend. For example, he knows that I went out to dinner with this friend and paid the bill (I invited him and it was a graduation gift for his master’s degree). My ex has been telling me that I’m so cheap that I paid for a man’s dinner and still let him nail me afterwards. He wouldn’t know any of those details unless he was listening to my convo or unless my friend told him, which my friend would have zero reason to do. They don’t even know each other.

The only way my ex could possibly know any of this is by listening in on my conversations. This friend of mine has only ever communicated with me via iMessages, Instagram, and FaceTime. I have changed all of my account passwords multiple times since our split. Two factor authorization is enabled, and I have been on the phone with Apple as they walked me through checking to see if other devices were signed into my Apple account and to check for unrecognized apps installed on my phone. Everything was clean. I have also checked what devices are connected to my WiFi and didn’t find anything suspicious.

The only other device he can use to monitor me is the ring app on our front door. I never have phone conversations near the ring app so it’s impossible that he would have heard something on there. Could he have a recording device hidden somewhere? I haven’t been able to find anything.

My lawyer told me to call the cops and have them check for a device within the home to see if he’s listening in, which I did on Monday. They weren’t able to find anything. I don’t feel safe in my home and feel that he is constantly watching me. He’s trying to pile up whatever evidence he can to try to make a case for himself in court.

Thoughts?