I try to keep in my mind the simple question: Am I trying to do good or make myself look good? Too many of our responsibilities get added to our plate when we are trying to please people, impress people, prove ourselves, acquire power, increase our prestige. All those motivations are about looking good more than doing good.
You can't please everyone. When you're too focused on living up to other people's standards, you aren't spending enough time raising your own. Some people may whisper, complain and judge. But for the most part, it's all in your head. People care less about your actions than you think. Why? They have their own problems!
Mental prayer in my opinion is nothing else than an intimate sharing between friends; it means taking time frequently to be alone with Him who we know loves us. The important thing is not to think much but to love much and so do that which best stirs you to love. Love is not great delight but desire to please God in everything.