Be a IT manager or a developer?

You want to be a programmer/developer and not a manager? I don't blame you. So do that.

If your current employer is saying "take the promotion or leave", and if you REALLY don't want the promotion - leave. It would be best I suppose if you got another job to jump to. But you could also work for yourself, or get setup with any of several referring agencies in your area ("consultants").

It's your career, and your life. Take charge.

Why do you "have" to be a manager?

Not to get too philosophical on you, but personal freedom, even when threatened up to death, is not given, it's taken.

Do whatever the hell you want to do. It's your life! Live it! Breathe It! Don't trust anyone who tries to convince you otherwise unless you WANT to sub-exist as a lifeless drone for others- because all they are doing is taking your power and freedom for their own gains. Don't let them have the one thing you really do have any control over -your powers of will and choice.

If you love to program: PROGRAM! Don't ask, Do. I'm sure you will do it well when you grab the big old Bull of life by the horns and flip over it's back 'cuz it really ain't that scary once you get the hang of it.

Just my two cents......