What do our MPs actually do?

Our local federal MP has announced he is retiring at the end of this term in parliament. He has come in for some criticism for that. "He's only 48!" "He's a rat deserting a sinking ship." "He's just served time to get a pension." "He's never done anything."
Some of the other comments about the story on another media website were far worse - the sort of libel I have come to expect from people who use the site as a place to hurl invective at the current government without any regard for the facts. 
I knew this man before he was an MP. I have known him for about twenty-two years. I will admit I was surprised when he was pre-selected for the seat because he is not a noisy, outspoken sort of person. He isn't the sort of person you think of as being an MP. He's actually a doctor as well though - and I think that may explain it. He listens and then acts.
He was never a minister but he worked hard behind the scenes. He was on the inevitable committees. He lobbied for funds for projects in the electorate. He dealt with problems brought to him and he often did it in a very personal way. He has been fiercely loyal to his electorate too.
That should count in this electorate because the state MP betrayed the electorate by effectively moving, without any consultation, to the Opposition. It added to the work load of the federal MP when people simply don't trust the state MP and won't go to him.
He has a young family and he has had to be away from them. Now that his son is heading towards his teenage years I have no doubt that they want to spend more time together. 
When he might have been watching his children play sport he was standing in shopping centres at "listening posts" - often being abused by those who do not like his side of politics and also being criticised for not doing the impossible. 
I know he has been putting in about seventy hours a week, sometimes more and rarely less. His wife says she knows what he looks like - but only just. It has been hard work for her as well.
And now he is planning a return to medicine. He will have some catching up to do after all this time - and he knows it. 
He will go on listening to people and trying to solve their problems.
And I wonder if the criticism of him is entirely fair. No, he wasn't a high profile, noisy MP who was always seeking publicity with a press release. He was never a holder of the highest offices in the land. 
But he did do what he was elected to do. He represented the people of his electorate and helped them where he  could. I wonder if all those high office holders can say the same thing?