Given his age it is not an unreasonable course of actions to end his life instead of spending his last years behind bars.
Please, he was a relatively young man, and regardless of what his sentence might have been, his life would have been interrupted for a time, but it wouldn't have been over, and he wouldn't have spent his "last years behind bars." A desperate and severely depressed person does not always weigh alternatives, or deal with stress, reasonably, and at least one person who knew Thom, recently posted that he was very depressed.
And you have no idea what finally made him end his life, any more than you really know what happened the night of the accident, despite your previous endless speculation regarding that. You know nothing about the man. He may have been dealing with a number of issues, in addition to possibly facing prison time, that just overwhelmed him.
It is indeed a sad outcome as two people lives ended as a result of that night not one.
It is indeed sad, particularly since neither of those lives had to end. That's part of the needless tragedies that are a consequence of drinking and driving.
And, based on my own experience with a friend who committed suicide, I know that some of Thom's friends and acquaintances must be feeling not only grief, but also some guilt that they hadn't done more to try to help him, because that's also a normal reaction when someone you care about takes their own life. I feel for them too. The ripple effect of what happened that night last December has affected many lives.
I hope this thread has served a useful purpose. If it makes at least one person not drive after they have been drinking, it will have done that.