I found this site,might be able to help you!
http://ukmoths.org.uk/top20.php
You could try to help it, but it will probably not make it. Those little guys aren't that resilient. The best thing I would do is put it out in a tree and let it be. If you believe like I do, it will be ok. Sometimes you can kill it just from stressing it out by touching it, but I think it's great you care about creatures like that. I'm the same way!!!!!!