Let me sum it up -
- dating for 5 years. Engaged for 3.
Due to some visa issues we couldn't get married sooner. Were almost everyday on skype, SMS, email, phone calls etc for 2 years. Met 6 times, during those 2 years for at least 2 weeks at a stretch.
- Relocated back to the US to pick up where we left off.
- Was told that we couldn't move ahead any longer because I did not want children and he did.

I have never wanted children, and he knew it when we started dating, when he proposed and throughout. I have never wavered.
But now he wants a sabbatical from me. He says it is not a break-up, but just a break he is taking from me. He wants to figure things out.

I then agreed to have children, but other reasons have cropped up, as to why our relationship will never work. None of the reasons are issues that he was not aware of.

Is he just making excuses? Did he make up his mind before I returned to the US? And now he is coming up with reasons to build his case?
I have heard the classical statement - "You are an angel, you couldn't have done things any different. But my gut instinct says that this won't work".

How do I get over this?

You get over it by stopping all contact with him and allowing your heart to heal.

Is he making excuses? You know him a lot better than anyone here. If you feel that he is, you're probably correct. Perhaps agreeing to have children only to make him happy makes him uneasy.

When did he make up his mind? Is he making up reasons?

You have been in a long term relationship; you are or have been engaged.

Ask him if you need to know these answers.