Help with mac startup crisis

[macman18]

Hello everyone. I am having a problem with my relatively new MacBook pro 17' intel i7. When I start up the computer, a loading bar appears under the apple logo. When the bar is complete I get to the screen where I enter my password. After inputting my password, a white/grey screen flashes momentarily and I am taken back to the password input screen. Restarting has no effect and neither does clearing the PRAM. I tried to start in safe mode by holding the shift key at startup but the loading bar problem still occurred. Please help! It should be noted that I used bootcamp to partition my hard drive and install windows 7 and that operating system seems to be starting up just fine. Thanks again for any help.
Some additional information:
1. I am currently running Lion.
2. Problems started occuring after an update to my Windows 7 OS.
3. Every time I try to restart after my password/blank screen loop, the screen goes white and I have to force shut down. It may just be me being impatient but I seems to get stuck on that white screen when i try to restart.

 

[Kaveman]

Try and Start with Command - R and reinstall OSX in place.

Note: Its always good to have an separate Admin Account and to no run as Admin.

 

[macman18]

Try and Start with Command - R and reinstall OSX in place.

Note: Its always good to have an separate Admin Account and to no run as Admin.

I tried that but when it got to the part where I select the disk that I want to install it on the only ones that were available we're my bootcamp and the recovery hd and both were locked.

 

[Kaveman]

About your only option is to go in via another Mac with your MacBook in Target mode and see if theres anything that can be recovered. Sounds like Windows 7 update has stuffed your Mac Partition.

You may need to take it to an Apple Service Centre near you.

 

[macman18]

About your only option is to go in via another Mac with your MacBook in Target mode and see if theres anything that can be recovered. Sounds like Windows 7 update has stuffed your Mac Partition.

You may need to take it to an Apple Service Centre near you.

Alright I guess I will have to see if Apple can help.