Like Jish, I also couldn't take Lexapro at night b/c of sleep issues. Most of the side effects did wear off for me after a couple weeks, but I still felt like it affected my sleep. I did MUCH better taking it in the morning. I just went back on Celexa and have been having some insomnia issues even though I'm taking it mid-day. When I'm over the nausea side effect, I'll switch to taking it mornings. Interestingly, my practitioner said Lexapro and Celexa usually have a slightly sedating effect and make people sleep better. Definitely not my experience.
I hope you find a drug or combo that works to help your anxiety, sleep, and depression soon. Warm wishes.