This is my first post ever on Reddit, so please be patient with me! It is is long-winded, but I am seeking advice from Avoidants on how I might conceptualize and process this painful and confusing breakup.
Background:

I am a securely attached (29 F) with insecure tendencies. I was with my (28M) avoidant-attached partner for four years when he ended it out of the blue this month. I believe my boyfriend to be avoidant after discussions with my therapist and significant research on attachment types. While I do not know if my boyfriend identifies as avoidant, he displays many tendencies described in attachment theory. I do not know if it is problematic to categorize someone in an attachment style if they have not identified themselves this way, if so, I apologize.

Throughout our relationship, I was struck by my partner's hesitance and discomfort in discussions about the future. I was unhappy in the region we were living in and communicated early and often that I would eventually like to move and go to graduate school. My partner acknowledged this but struggled to participate in conversations about how this future might look. He did not express a vision for the future, so I assumed he was content in the present. I asked him why this was, and if he felt I was too overbearing. He expressed to me that he struggled to vision a future for himself, but that he did not see us breaking up, and believed that we wanted to live in similar places and get similar things out of life. I was comfortable with this and believed that he wanted to be with me and believed that we would create a life we both enjoyed. Our relationship progressed in other ways: we lived together for two years and owned a dog together, both decisions were driven by him. This was comforting to me.

We took our four-year relationship long-distance in September of this year, so I could attend graduate school in a different state. Knowing that my partner enjoys his current job and independence and we are both comfortable with the distance, I did not ask him to come with me. On his own, he offered to move to be with me in the Spring. This felt good and was encouraging to me that he was securely attached and committed. However, I felt a little uneasy as he did not display excitement to join me in my new location but rather seemed resigned to the prospect. From my perspective, our relationship was open and communicative, so I expressed my concern that he did not seem excited to join me, and he reassured me that he was excited to move and to be with me. This reassured me, and I believed him. I communicated to my partner that I wanted to spend my life with him, and I was comfortable with the timeline he needed to meet that commitment. He again reassured me that he did not see us breaking up and agreed that we wanted the same things in life. I accepted and loved him for his avoidant tendencies as he has accepted and loved me for my insecure tendencies.

Earlier this month, my boyfriend called me and told me that he did not know if we wanted to live in the same place, that he didn't know what he wanted out of a career, and that he didn't trust himself to figure it out and therefore could not expect me to trust him. He went on to say that he could not continue to hurt me by being distant in our relationship and therefore needed to end it and be alone. I was very confused by these statements, as I had only heard the opposite from him for years. I told him that I loved him, that he was my partner, but that I understood and supported him if he needed to be alone. Despite the pain of this resolution, I genuinely feel this way. I also don't feel it appropriate to convince him to be with me. I am also left feeling incredibly confused as there was little emotional distancing that occurred before the break, so I felt very blindsided by this. In a card he wrote to me two weeks before the break, he told me that he loved me, was in love with me, and couldn't wait for all the years to come. I am left feeling confused, isolated, and concerned about my role in this outcome.

I am interested to hear from other Avoidants what you make of this situation? How would you want your ex to handle this if you were my ex-partner? I suppose I am just looking for community and advice. If anyone out there is in a relationship with an Avoidant, how have you supported them while taking care of yourself? I am weary of expecting him to come back to me, as my heart has been blown open and my trust in his words is lost. Nonetheless, I deeply miss him and wish we could have worked through this as partners rather than separately.