I am not planning to bail at this moment either, but I have to agree with what Fairy said. If the one fact that is being withheld is a huge factor in this case and we are all way off, then we might be spinning our wheels here or at least be able to eliminate certain ideas.
Heres a few examples of withheld information and where that would come into play:
1) If there was another camera that showed Steven walking up to the SUV and giving the Blond woman inside a kiss and then driving off with her. That would definitely eliminate some of our other theories (the gay theory, the suicide theory, etc.). Also, it would seem he just drove off into the sunset and there is no law against that. The family may want to withhold that information because even though they know he left voluntarily, they want us to keep looking for him so they know where he is.
2) Maybe the hard drive was searched and the information being withheld is what was found on it. Steven could have been looking up flights to Brazil a few days before he left and noone can locate his passport now. I think information like that would change the way we are looking at this case.
3) If there was a note left in the car that we don't know about that said "can't live like this anymore I am sorry." The family wouldn't know if that meant suicide or starting over, but they wouldn't stop looking until they knew and would want the publics help in doing so.
4) He does have a mental illness and was taking medication that was left at home. In that case some of the girlfriend/boyfriend theories would go out the window. The SP theory would go away. The focus would be more directed to things like the IHOP sighting, homeless shelters, etc.
Hopefully my post makes sense and kind of explains where we are coming from. I respect the decision of the family to withhold what they need to if it will help find Steven.
I just don't want to be focusing on Las Vegas if you know he hopped on a bus to Michigan