We all have our ups and downs. This happens at the best of times. The problem is, when we go for an extended down - like we all have done - the downs get magnified.
You're on your way to seeing/feeling the downs in a less pronounced way. Don't let comments from other people like your SIL (who I'm sure had the best of intentions) deflect you from your path.
This thread is gettning too big, so I'm moving over to The Boxer