You didn't say how long you've been on the Lexapro, but perhaps you need to adjust the time when you take it.
I took Lexapro and my mornings were the worst. I was taking my Lex first thing in the morning. I gradually adjusted to take it at night, and it really helped a lot. Some say Lex causes sleeplessness for them, but I didn't have that problem.
I developed a routine that I did each evening. I took a nice relaxing shower or bath, took my lexapro with a glass of milk about 30 minutes before I went to bed, then read or watched a "boring" TV show. The hot shower or bath allows your body to cool down, as it does naturally when preparing for sleep, and the milk helps your body not to wake up because it's hungry. Doing this routine nightly, trains your body that it's time to relax and sleep.
Good luck to you, and I hope you are able to eliminate the morning dread.