Sounds like he's scared if you ask me. And confused, but buying a house, going THROUGH with buying a house that will not work for two is not something easily undone and it would be expensive otherwise.
This is strangely earily familiar to my best friend's relationship where she was planning a log cabin with her boy friend - even selected the front door, etc., but then he dumped her.
Ironically, she bought a house just as she started dating a new guy (like she bought it on their 2nd or 3rd date - he's a carpenter, so she had him go through the house with her to make sure it was solid). 4 years later they got married and still live in that house.

