My MacBook Pro doesn't boot up Mountain Lion anymore :(

[negativzero]

I went ahead and installed windows 8 over bootcamp a few hours back. But now I can't get get back to ML anymore. I tried holding down option while booting up and selecting my ML partition but it boots up windows instead. Likewise holding option and selecting windows boots my Windows 8.

I'm pretty sure ML is not deleted in any way because I can still see my ML files while browsing them on Windows 8.

Anyone with any ideas on solving this?

 

[duffman9000]

I've done this before. Try booting a OS X disk and then use the disk utility to select the boot disk. Reboot and it should be done.