more clutch related problems ...

I've read all the posts related to clutch problems and still don't seem to find the right answer so here it goes....
bought the car a year ago 04 spec v took it to the dealer car passed with flying colors they said that the clutch should have 50% of life left car has around 140k miles on it but the engine was rebuilt by nissan at 60k ...

after 3 months of taking the car to the dealer as I was driving I noticed that the clutch pedal was acting weird suddenly it wouldn't come out..... took it to the mechanic and the screw that is underneath the master cylinder was kinda broken so all the fluid was gone..... at that time I changed the master and the slave just to be on the safe side......

2 months later.... I start to feel the clutch pedal acting weird. I stopped to check the fluid and saw that it was getting low so I topped up the fluid and kept driving for an hour... when i got home and I saw that the fluid level was down again so I knew there was something wrong..... took the master out cylinder and got a replacement.....

1-2 months later same problem I start to see that the fluid is starting to come down and while I was driving and changing gears I pressed the clutch and heard a click sound (like something getting broken) so I stopped went to check the fluid and the level is getting lower faster so I have to fill it up constantly ....sometimes when I push the pedal all the way down it may get stuck there and I have to use my hand or my foot to pull it back up.

Now I don't think that the three master cylinders were defective I feel that there is something that is making the cylinder work harder than it should like extra pressure or something.... sometimes when I'm driving I feel the pedal getting harder to press....

thanks for reading the long posts any comments would be greatly appreciated