I think it is reasonable to donate most of them but the things that are just a bit too big but not crazy big I think you should keep in an attic or storage space just in case maybe that is an unhealthy way of thinking but sometimes it's good to have an extra pair of jeans around.
Donate but keep 1pc to remind you of where you were at and never to go back to that dark place
Business clothes, check the area for back to work programs for women. I donated to Women in Distress here and it did wonders for the ladies who needed them to work, or apply for a job. Anything gently used can be used by another. Also, if you want, you can find a consignment shop near you and either swap out for clothes, or sell on consignment!!