Drink driving can not and should not be condoned in any circumstances. It's selfish, and bloody dangerous, putting innocent lives at risk is not acceptable in any way. Mental health problems or not. He should be punished for that accordingly by law, whether than be prison, fine, loss of license, awareness course, all of the above, whatever.
That part of it aside, I do like Ant and Dec for their entertainment value. I think they are very good at their jobs and are likeable, funny people. I hope it isn't the beginning of the end for them. Dec has done nothing wrong and doesn't deserve to have his career flushed away. After this long it just wouldn't work with either of them being individual presenters. Hopefully after some more time to address his problems, Ant will bounce back. Other celebrities have done similar and far far worse than he has, and managed to continue their career just as any none famous person will have been able to.
I think Ant should be cut some slack (drink driving aside).
Have a think how much he's been through. If he was posting on Mumsnet as an anonymous person about his relationship and surgery issues I bet most people would be filled with sympathy.
Botched knee surgery
Immense pain due to knee
Reliant on very strong painkillers to get by that are known to be addictive
Addiction to said painkillers
Drinking more because of above problems
Marriage problems
Struggling to conceive
Going to rehab
Thrown straight back into high pressure live tv role
Filming for other shows
Knowing that the nation is watching his every move on tv
Separation from long term wife
Having everything reported on constantly
He's not someone who is pictured pissed falling out of clubs and always over sharing about his personal life. He stays out of the way when he's not doing his job from what I can tell.
No amount of money or privileged life style can help someone who is struggling with their mental health. That's got nothing to do with it, plenty have made snarky remarks about him being able to retire and not struggle for money. Maybe he values his career and would rather get back to doing that than just sit around on a pot of money.
Good luck to him, I hope he has had a big enough shock to knock some sense into him that he needs to sort himself out for his own good and everyone else around him.