need honest opinions!

My baby has been exclusively breastfed since day one. He's almost 6 weeks old, and I've been put on lexapro for ppd. Lexapro is the only antidepressant that works well for me. This is considered "probably safe due to lack of safety studies" for breastfeeding. So, I've switched to formula because I don't like the unknown. My supply is still up so, I need to decide now what I want to do! Would you continue to breastfeed? Would you switch to formula due to lack of safety studies? Would love honest opinions!