While it is disappointing, of course, to Brokeback fans particularly, that Jake made no statement, if we look at it in the context of Heath's death, his lack of a statement is neither peculiar nor ominous; nor do the number of other statements made by other actors, directors, producers - have any reflection on Jake's decision to not make a statement.
All Jake has done was not divulge to the media his reaction to Heath's death. We don't know what expressions of sympathy (or of grief) he made privately, or to the family. We aren't told what he felt about the events. However, what we can say without a doubt is that media attention has been on Jake and Heath ever since they were cast in "Brokeback", they went on endless press junkets, were photographed hundreds of thousands of times together, and long after the film was out of theaters their subsequent roles and film projects were overshadowed to the point where major press events about their new films came out and interviewers still focused on what it was like for them to film the kissing scene, and how they feel about being gay icons, etc. etc. I think that considering this industry - and public - fascination with Jake's sexuality (which was there before he took the role of Jack) and the way Brokeback loomed over his subsequent career, it is no surprise he doesn't want to talk about it anymore. He has no obligation to. Nor is it any surprise that he would not want to state his feelings publically.
If you look at the statement issued through Michelle's publicist, the message was a plea for privacy and to be left alone by the press. She did not give an interview and did not talk to a reporter. Kim Ledger's statements to reporters were mostly to avert a mob scene at his funeral, and unavoidable. The set of "Brothers" put on extra security to keep photographers and reporters away from Jake. He went into virtual seclusion for weeks. He doesn't want to talk about Heath, and has not wanted to be confronted by reporters and photographers.
I find myself wondering just how tough it is for someone to live and work as these actors do, stalked and photographed when they step out for a coffee or a sandwich, not wanting to make statements as they go about their daily lives, trying to maintain some sense of privacy and normalcy in the course of shooting films. It must be maddening to them. My personal opinion, having thought about this a lot - is that Jake's decision to avoid reporters and not make a statement was in order to damp down the hysterical frenzy surrounding Heath's death, and to stay out of it so he could finish his film and move on with his career.
Also, I believe one report did place Jake at one of the L.A. events.