Thank you for choosing this website. I'm sorry to hear you're having such difficulty in your relationship. Two years is a long time to know someone and have a commitment for a wedding next summer makes it even more tragic.you seem very puzzled over recent events and his change in attitude but most importantly his lack of communication.
I can only think that because this was a long distance relationship he met someone else and did not have the courage to tell you. Sometimes there is simply no substitute for spending every day with someone in terms of getting to know them very well. Even though you may call him on a daily basis or text them it is still a poor substitute for daily face to face contact.
In terms of recommendations I think you are simply being too polite. You need to be much more forceful with him and express some of your anger and frustration. This man needs to know that he is abandoned you and lacks the courage to even tell you that he hath met someone else. It is only by expressing your feelings that you will be able to process them and see his reaction.this may in the future teacher not be so willing to trust someone else.
I see that your currently off-line and I am very interested in your reaction to my answer