Hi, I'd like to help you with your problem.
I can understand why you felt upset by your boyfriend suddenly deciding to move out. From what you said, I believe that it is not so much that he wanted to buy something, but that he left you out of the decision totally and also did not tell you about it until after the fact.
It is easy to see why you feel this is a break up. After living together, you are making decisions together and sharing a home. This is a very intimate situation. When one partner suddenly leaves, it feels like they are also leaving the relationship.
The fact that he left you out of the whole search and purchase of a home certainly speaks to his feelings about the relationship. He may very well feel that it is not over, but he is giving the appearance of not being as committed to the relationship as you are.
If you and he still want to continue the relationship, there needs to be better communication about feelings and intentions. Also, I recommend therapy as a way to improve communication and to also get a better idea of where the relationship is at this point. If he is unwilling to go with you, go yourself. You need guidance on how to handle this relationship and also to help you get over it, if you so choose.
I hope this helped you,