It's actually quite simple: Ford was successful because they mostly delivered products the market demanded in a cost-efficient manner. GM and Chrysler mostly delivered products the market did not demand, and they obviously did so without being cost-efficient. To put it even more simply, Ford the winner was forced to help bailout the losers.
I can understand the GM bailout, and do not necessarily disagree with it, but the Chrysler bailout was wholly inexcusable. Their assets should have been liquidated to the highest bidders. They had already been bailed out once before. Fool me once, shame on you. Fool me twice, shame on me.
A good part of why Ford was able to avoid a bailout was they went to a high leverage position before the credit crunch, which gave them the cash to ride out the downturn. They planned for the possibility, while GM did not and was unable to secure the financing they needed once the crunch hit. Considering that Ford shareholders have made out much better than old GM shareholders have, to say the bailout helped GM disproportionately would require not using a shareholder-centric view of what a company is.
As for Chrysler, the fact is that if Chrysler had gone into conventional bankruptcy, its factories would all be closed now, and those jobs and those of their suppliers and dealers would be gone for good. There has been and continues to be an oversupply of production capacity in the auto industry. Keeping Chrysler running until it could be taken over by another company was the best way to keep those jobs in America. It likely would have been better if it hadn't be Fiat that took Chrysler, but no better option presented itself.