Hello kes8529. I am so sorry that you're going through such a confusing and painful situation

Relationships are difficult, aren't they? If only it were enough to love someone so much and then be loved in return. With the background you mentioned with your father, I imagine trusting and attachment are quite complicated for you. Understandably. Is your mother in your life? Is she supportive?
You mentioned that you are talking to a psychotherapist. That sounds like a strong and intelligent way to deal with your concerns. Not easy, either, I've been there. May I ask how it's going for you? Do you talk about your bf with the therapist? Has he/she given you any strategies?
I'll share some ideas. I'd like you to try an exercise if you are comfortable with it. Find a nice quiet place in your home while alone. Grab a notebook and pen and put it next to you. Close your eyes for a few minutes. Try to imagine your life if things don't work out with your bf...if don't see each other anymore. While you're thinking about it, pay attention to how you think and feel in those moments...body and mind. Grab the notebook and write that down. "When I imagine life without him, I feel _____ and _________ and I think __________. When I imagine never seeing him again, my body feels ____________." When answering those questions, focus only on you and your thoughts/feelings, not his. If you do that, I think you are may get a few answers for yourself which will be really helpful moving forward. You can take the answers to your therapist and start unpacking the thoughts and feelings.
I tried to read all of your posts on the thread but I apologize in advance if I missed or misunderstood a piece. I think you said at one point that you are not trying to change the man. Do I have that right? Honestly, and zero judgment from me here, that sounds like exactly what you are trying to do. And I don't think that will lead you to a path of peace and joy in life. We cannot change anyone even if they say they want to change for us. I am also concerned that he doesn't sound (I obviously don't know him) to be completely honest and direct about his wishes and feelings. To me, it sometimes sounds like he tells you what he thinks you want to hear.
Then on your side, it seems like you are trying to psychoanalyze him. I understand that you want to relate to him and the situation is so confusing but you aren't trained in analysis (correct me if I'm wrong) and we cannot read other people's minds. You told him you know the way he thinks and why. I would encourage you to take a step back from that. I don't think you can know exactly what he thinks and why. Can anyone truly know your thoughts?
This is obviously very painful for you and you have my support. At this point, I recommend continuing your own therapy and trying to bring your thoughts and goals back to you. What do you want for your own future? How's work? Any close friends to chat and have a laugh with? Are there family members you enjoy spending time with? Hobbies? Self-care?
I have the impression that maybe you believe your future happiness is dependent on being with him. One thing I've learned the hard way in life is that we cannot look to others to create happiness for us. We need to seek our own joy and peace as an individual....we need to honor and love our own Self. After we have achieved that, then we can share our happiness with another person who has also done the work on their own Self.
You mentioned low self-esteem. Were you aware of that prior to the relationship with your bf? What is your inner self-talk like? Have you ever written it down? How do you think and feel about yourself (not in relation to the bf)? Are you familiar with Inner Child theory? It may be worth a look.
I hope you find peace. And I really hope your therapist is kind and insightful.
I wish you a bright future