RainbowMM: you were in a rebound relationship
You guys had a strong connection (with the ex bf). But it is a rebound relationship for him and he has changed since 1.5 years ago. This is why he gives you no commitment. Please realize people in the rebound relationship act differently than people in a healthy relationship.
I think you need to realize that and admit things are very different now for your ex bf. Move on and be careful to not get into another rebound relationship.