External HDD not working with my computer only

ok...backstory:

I have a WD external hard drive with 2 partitions, a FAT32 partition and a normally Mac-formatted partition. I use the Mac formatted partition for Time Machine and the FAT32 partition for miscellaneous storage. My Mac is a February 2008 2.4GHz MacBook.

Everything was going fine until about September until my hard drive suddenly wouldn't connect to my Mac or my friend's computer running XP. He suggested that I take the drive out of the enclosure and he lent me a separate SATA-USB adapter to use. This worked, and I was using it for a while. However, my friend soon needed his adapter back, so I retried the original enclosure and it started working again.

This was about a month ago, and it has been working fine ever since until yesterday, when I accidentally knocked the power cord out while it was performing a Time Machine backup (stupid, I know). I think i finally killed the original enclosure because it won't even spin anymore, but when I borrowed my friends adapter again, it worked fine on his computer (it recognized the FAT32 partition, but obviously not the Mac-formatted partition). However, It still will not load on my Mac. I tried it on several different computer running both Vista and XP - including my boot-camped XP partition - and it worked fine on all of them. I have not been able to try it on any other Macs.

If anyone has any ideas/thoughts/suggestions/anything, I would really appreciate it. I will report back when I get the opportunity to try my hard drive it on another Mac (probably tomorrow afternoon), but I wanted to post now in case anyone's seen this problem before.

Thanks in advance!
-John