Nope. It's his fault that he keeps falling into the same rut. That is a lesson we must learn on our own, I'm afraid. Is he a teen? In the early teen years, it's almost impossible to have anything BUT a crazy girlfriend or boyfriend. How can we expect rational or adult decisions from someone who has an incompletely developed brain? :)

At most, I might consider asking him if he searches out the crazies and likes the wild ride, or if he actually wants something different. If he does indeed wish not to date the crazies, I might suggest steps that would move him in that direction. Otherwise, let him experiment!

You can try to guide him.. to better dating possibilities or locations to even pick up better dates.. But maybe its not commitment he is looking for but is just looking for interesting short term dates. Many at first will date many of the wrong people subconsciously deliberately.. It sounds like he swinger who is attracted to swingers.. Meaning people who date without a long term or a short term commitment just for fun... It maybe a phase it maybe his preference.. You can try to help him if you want to.. But no matter what you do,, You can not change a person's preference for who or what they are attracted to.... You could give him suggestions of how to protect himself better in crazy type of relationships... And.. Not all who appear crazy to the outside world are necessarily as crazy as we think... Like bipolars for instance.. I have meant some crazy ones that I would have a restraining order on in a moment.. Then I have met people with the same disorder you can not tell they are bipolar.. unless you look at their medicine cabinent as they learned to manager the illness. Bipolars get a bad rap as many others with mental illnesses do.. Based on what the ones who are refusing to improve their lives or trying to manage it do... You can try to hook him up with a nice girls if you want to... But.. If he is not interested do not take it personal.. people will go towards who they are attracted to for their own personal reasons. Some date really wild people for most of their lives.. then all of sudden settle down and get married with a nice couple.. and are glad they met that right person..

There is an old saying.. "Maybe we are meant to date all the wrong ones first, so when we find the right one.. We enjoy it more" - anonymous.

But only your brother like everyone else.. Can enjoy and find that right one. He just may not be ready for commitment or may enjoy wild swingers types of relationships.