There's a good possibility that your real problem is a deficiency in EFA's (essential fatty acids)if you are anorexic. They are called essential because you only get them from your diet. Try evening primrose oil. It worked wonders for me within a month and I've never gone back to the horrible symptoms. For me the mood swings, irritability and teariness were the worst. This is totally gone and I hardly know my periods are coming. You'll want to take it daily until you build your body's stores back up.
Do you mind if I ask what it is you are calling a mild antidepressant? I may have some further information for you about why you don't want to ingest this drug.