Never be embarrassed about diversification. In 2012 Microsoft could have been found to be cooking the books and $30 would be a lot. Or they could have hit a hard patch, lost stock value and laid you off and you'd be out income and savings.
You're right about that! Remember that in 2011, Microsoft was considered a zombie-company. No one expected it to grow in value.
Most helpful way I know to think about this is: if you’d been given that stock as cash would you have bought the stock. Breaks the cognitive bias of already holding the stock.