I've been on meds the majority of my adult life as well. I went off them a little over a year ago. I still have one for as needed anxiety, but I no longer take anything all the time. I hit a few rough spots, but for the most part have done really well.
What has worked for me is journaling, or blogging when I am feeling good, and looking at it when I am in a deppressive fit. It helps me remember that this is not me, and not who I want to be. IT's the chemicals and my own inability to deal with things. Once I get a grip on how strong and confident I know I am , it makes coming out of it a lot quicker and a lot easier.
Good luck to you! I know weaning can be hard. I hit one of my worst patches when I came off the meds completely. I was about to go back on them (the Karma/Cricket drama first started about 2 months after I was off my meds. Great time to find out about a bunch of affairs!!) when I reminded myself that this is exactly the type of thing I will have to deal with and I can do it. Once got through the withdrawl symptoms I started feeling a lot better.
Hope it is a smooth process for you and it all works out!