How to start a difficult conversation

Me and my husband went through a rough patch with awful communication. I tried to get therapy and better myself, whilst looking at ways to improve our relationship. He ( i snooped) sought porn and searched dating websites rather than discussed his geeling with me. Turns out, after finally having a convo, he was ashamed of his sexual needs and didn't think I'd be up to trying out some spice. Now, he doesn't yet know I k ow about the dating sites and the porn. I also found another email that he must had used for these accounts. He is the happiest he has been, very sweet, and everything since the conversation. But, I'm harvesting this knowledge and I want to talk to him about how he has hurt me and broken my trust. If he has cheated, it is not obvious at all as he is always at home. But, I want him to not use his phone as much, I want him to delete all these temptations, and I was complete transparency if we are to survive this. I am heart broken. How do I start a difficult conversation like this, without ruining the repair we had done these past weeks?