Terrified of leaving my little girl :(

My little girl is 20 months old and I have to go back to work next week but I'm terrified of leaving her... since she was born I haven't left her for more than an hour and she still currently nurses ALOT, not really for the milk but mostly for comfort and I can't stop worrying about how she will be, I can't cope with the fact that she could be crying for me and I'm not there, shes very attached to me and rarely leaves my side!... that all she wants is her "milkies" and again.. I'm not there to give it to her, or how will the staff know what she wants? She doesn't talk much and is quite shy, how will they be able to soothe her? What if she's hungry? Thirsty? Tired? She won't be able to verbally tell them what she wants:(

ugh I just have all these thoughts going round in my head and it's upsetting.. I'm abosuelty terrified of leaving her. I guess my reason for posting this is to get some advice on how to make this easier for me from people who have been there before... and to maybe tell me it'll all be okay :(