Dear Economist: Should I forgive my selfish ex-boyfriend?

I was living with my boyfriend when he got accepted to a very good university in London. He convinced me to go with him. I applied and got accepted to another very good university to pursue a masters degree that I long dreamed of. He broke up with me before I knew I had been accepted, arguing he wasn’t prepared to carry the responsibility of me leaving a life behind to go after him. Of course, it was his idea in the first place.
He has been living in London since September. I have just arrived. I still love him, but I think he has been very selfish. Should I forgive him and look him up? Human selfishness and economics have always walked hand in hand. I would love to have your advice.
CP

Dear CP,

The whole episode seems to have been very good for you: at your boyfriend’s urging, you followed your dreams and now you are realising them. Wonderful.

However, this happy fact does not translate into a compelling reason to renew the relationship. Normally I advise people that they should ignore “sunk costs” – to put it another way, there is no use crying over spilt milk. In this particular case you should ignore the “sunk benefits”. Forget the fact that it’s all worked out well, and focus instead on what this story tells you about the prospects for a happy future together.

If your boyfriend is not rational then his behaviour is self-destructive and self-obsessed. Even worse, if your boyfriend is rational – as economists usually assume – then he seems simply to have been opening up an option (to have his old girlfriend in London) and discarding it when it had no value to him.

I’d guess he thought he could do better than his old relationship in London. I’m quite sure that you can.

Questions to economist@ft.com

The Undercover Economist: a guide

Publishing schedule: Excerpts from "The Undercover Economist" and "Dear Economist", Tim's weekly columns for the FT Magazine, are published on this blog on Saturday mornings.
More about Tim: Tim also writes editorials for the FT, presents Radio 4's More or Less and is the author of "The Undercover Economist" and "The Logic of Life".
Comment: To comment, please register with FT.com, which you can do for free here. Please also read our comments policy here.
Contact: Tim's contact address is: economist@ft.com
Time: UK time is shown on posts.
Follow: A link to the blog's RSS feeds is at the top of the page.
Follow on Twitter
FT blogs: See the full range of the FT's blogs here.