1996 Mitsubishi Galant Alternator Belt Keeps Breaking

About two years ago my power steering belt broke, my husband replaced it and then it broke a second time. He replaced the power steering pump and everything seemed fine. But about six months after he replaced the power steering pump the alternator belt broke. He replaced it and about another six months later it broke again. He then replaced the alternator. Six months later the belt broke again. He replaced the belt yet again. After this replacement the car started to make a squealing noise at start up and and would stop after a few minutes. Just last month the belt broke again and we ended up replacing the alternator and the belt again. Since then the squealing noise has been a constant. So I ended up taking it to the dealer ship. They said the belts were just loose and they tightened them up. The noise stopped for about a week. So I took it back to the dealer ship, they said the alternator belt was still a little loose and he tighten it up again. I no more got a mile down the road and the noise started again. So that following monday I took the car back up the the dealer ship. Asked them to check the serpentine belt tensioner and the bearings. He then told me that they were all fine and that I had an oil leak that was saturating the belts and thats why it keeps squealing. So I fixed the leek. Replace the belts. Then the alternator belt broke yet again this morning. If any one could please help us figure out what is going on it would be a great help. Thanks