Despite the latest troubles, I still count Mary and Byron as a Bachelor success story. They have lived together as a family for three years. Byron moved to Tampa so Mary could be near her family and her career. They bought a house there. Mary took up fishing with Byron and later embraced his sport herself. They or he bought the resort in TX on a wonderful fishing lake and Mary was going to get her TX real estate license.
They didn't get married; they didn't have children right away; they were together as a couple for three years. No matter what they decide to do now, that is a long realationship to come out of The Bachelor.
Sarah and Charlie were another success to come from The Bachelor. Whether they ever get back to gether (as most of us hope) or not, that too is a long Bachelor relationship.
Trista and Ryan - I don't think anyone will ever match them again.