Boyfriend (28M) Struggles with Boundaries (27F)

I'm a 27-year-old woman who recently experienced yet another breakup with my on-and-off boyfriend (28) after discovering he cheated on me—again. In response to the heartbreak, I began reaching out to other people and vented my frustrations about him to friends. When he learned about my messages, he ended the relationship, despite being the one who had been unfaithful. After a week apart, he returned and admitted he overreacted, expressing a desire to work things out. I still care for him and agreed to explore the possibility of reconciling, but I want to approach things differently this time. I made it clear that I don’t want us to slip back into old patterns right away. In past breakups, I tended to let things return to normal too quickly—like spending the night together and pretending nothing happened—without any real effort to change. So, I set a boundary: I’m open to dating and spending time together, but I don’t want to rush back into intimacy or overnight stays. (We just reconnected on Sunday). Instead of respecting my boundary, he’s pushing back against it. He outright told me that if I don’t "give in" on this issue, I shouldn’t be upset if he cheats again, implying that denying him intimacy would lead him to cheat. That statement really disturbed me. Tonight, I invited him to dinner because I still want to spend time together. At the end of the night, after walking me to my car, he asked if I was coming over. I reminded him of my boundary and declined. In response, he refused to kiss me goodnight and acted coldly towards me. Right now, I feel like he’s punishing me for wanting to take a thoughtful approach instead of rushing back into things. I don't believe I'm asking for too much—just some time and effort before we dive back in as if nothing happened. How can I maintain my boundaries while trying to rebuild trust with an ex who seems resistant to change?