I'm in a similar boat. Honestly, the way I've been trying to cope is just by getting through each day as normally as possible and lettings my routines carry me along. Continuing to act like everything is fine has been helping me realize that rejections really aren't the end of the world. Plus, a "no" isn't a "never", right? I've seen a lot of folks here telling each other to not take the rejections personally, and that they aren't necessarily rejections but redirections-- maybe that's what we need to keep reminding ourselves.
I hope you hear good news from UC Merced, and that you find your stride!