Being in recovery means being as honest with myself as possible, as well as with everyone else. In spite of my worst fears and awfulizing, opening up and telling the truth almost always turns out to be a freeing experience. Much better than bottling it up and sweeping my demons under the carpet. After all, I've got nothing to hide at this point.
The best part is that my relationships usually mend and grow when I'm honest with others, it opens us up to trust and respect.
And as far as you being like your MIL, that's a personal decision, you don't have to be like anyone if you don't like what they have. I think you know what the right choice is