Thanks for giving me all of the information. I am sorry to hear of all your pain around this. I am sure you are all of the wonderful things you say and say about him too but that doesn't seem to be the issue. He was very open with you letting you know that his feelings have changed a bit and he needs time to figure it all out. Even if things felt great and he proposed and you are wonderful, that doesn't prevent his feelings from changing or from feeling so much stress in his life, where being on his own is something he desires right now. The best thing you can do is to give him the time and space he is asking for...I know how painful it is and it is okay to let yourself feel all of it. You love him and want to be with him. During this time, live your life and do the things you love and hopefully this time apart can give him some clarity and make his way back to you.
Let me know your thoughts.