How can I, a 37-year-old woman, encourage my partner, a 45-year-old man, with whom I've been together for 15 years, to consider trying therapy?

I’m a 37-year-old female who has been in a long-term relationship with a 45-year-old male for 15 years. We’ve lived together for 13 of those years. Our relationship was strong until around 2017/2018 when I had an affair. I fully acknowledge that what I did was wrong; I regret not ending the relationship or refraining from the affair altogether, but I can’t change my past decisions. Now, over six years later, I realize that he still hasn’t truly forgiven me. While I understand he can’t forget what happened, I don’t believe we can have a healthy relationship if it continues to resurface and he can’t let it go. I’ve suggested individual therapy for him and couples therapy for us, and I’ve been working on myself through my own therapy for several years. This journey has helped me identify aspects of our relationship that I’m unhappy with, and I’ve tried discussing these with him. However, whenever I express my needs or stand up for myself, he accuses me of being a bully. On the other hand, when I disengage from the conversation because I feel sad, tired, or just want to avoid conflict, he sees me as playing the martyr. I’ve also expressed my desire to move to a different state, where my family lives, as I feel isolated here with only a few friends and no family nearby. I want to be closer to my dad and to experience my nephew’s upbringing. When I mention this, he interprets it as me trying to pressure him since I’m willing to go regardless of whether he joins me. My intention is to give him the choice about moving. Though we aren’t legally married, we do share a home, which means that if we decide to part ways, some logistics would need to be addressed together. I wish he would understand that individual or couples therapy could really help us navigate this situation. He seems to think I’m pushing him into something uncomfortable because he believes “men don’t talk about their feelings.” To clarify, he’s never been abusive, but I do perceive a passive-aggressive tendency toward my needs. I also sense that he knows how to steer conversations in a way that avoids him looking bad. I’m reaching a breaking point, but I’m not ready to leave because I still love him. **Just to emphasize, I don’t need him financially; I have a solid job. In summary, how can I encourage my partner of 15 years to consider therapy?