Hi adaw,
at first i tried supportive and understanding, this did not work. now i have turned rigid and angry and snap at her at every episode and reprimand her. amazingly she changed. she is careful of what she says is more loving asks for my advice. don't make snappy decisions and lies a lot less. looks like she wanted someone to take charge of her
you becoming angry when she is upset is validating for her. You reflect back to her what she is feeling. However the way you go about it is extreme and not respectful. It solves some problems but creates others. In the long run you want to arrive at mutual respect. Please check out the workshops on validation to learn how to validate negative stuff without going to these extremes.
Clear statements and directions are a good thing (keeping in mind the needs of our partner). In some way they work as boundaries to the universe of possibilities and threats. They remove uncertainty and reduce fear.