I ended an engagement at your age (a year and a half ago) for slightly different reasons, but like you, I was deeply unhappy. Also like you, I had to leave pretty much everything behind (almost exactly the things you listed!) and had to start entirely from scratch. It was terrifying...I hadn't been single since I was 20. And I questioned my choice and my feelings the entire time.

When I was trying to decide what to do, I went away for a weekend and unplugged entirely from my life. I spent a lot of time thinking, writing, mourning. I finally sat down and wrote a letter to him (but really, it was for me...I never gave it to him). In it, I listed all of the reasons I couldn't marry him. I kept this letter and read it when I was feeling doubtful...and it kept me on the path I knew I needed to be on.

I truly believe that when you know, you know. Trust your gut...if you have doubts now, they won't go away when you get married. Even if you can't quite put your finger on why they are there right now. If you still aren't totally convinced, then it sounds like you and your partner need to make a bona fide effort to follow through on the advice of your therapist. If you can't or if you do and nothing changes, you have your answer.

As for me, as hard as it was to put my life back together, I have no doubts whatsoever that I made the right decision. I have grown so much as a person and am finally starting to see the fruits of my hard work. I wish you all of the best!