Spayed at 2mos. Anorexic and lethargic

I adopted Sparrow, a roughly 2 month old kitten, two weeks ago yesterday as a college graduation present to myself. She came from the humane society, which tends to spay kittens really young. When I met her, it was love at first sight. I was drawn to her calico coloring and gentle temperment. I noticed that she wasn't playful, but attributed it to being frightened. 2 days later she had not pooped and had only eaten what had been forced on her. I took her to the vet after a really tough night (that I honestly didnt think she would survive) and they said that she had list half a pound from when the humane society weighed her, was extremely lethargic, and had anorexia. The vet sent me home with a/d and a huge doctor bill. She improved a little, but I decided to take her to a vet today. She has lost another half a pound (being fed nothing but a/d 5 times a day). There is nothing inherently wrong other than the fact that she has no appetite and does not understand how to lap water correctly. She is a wonderful little girl who loves kisses and has completely stolen my heart. She purrs all the time and seems to be fine mentally. Does anyone have any insight or suggestions for things I can do? I could really use some advise about how to make her eat and drink on her own

She also doesn't groom or play, but those may be related to the lack of energy.

Try all kinds of tasty things---tuna, sardines, chicken/turkey baby food (make sure there's no garlic or onion added), cooked meat, etc. Cats have a tendency to get "stuck" on something, so not eating sort of becomes a habit :/. Once you get her eating on her own, even a little, she should start eating normally after that.

How much does she weigh now? If she's lost an entire pound, at her age that's probably half her weight! How much A/D is she getting? If she's getting enough she definitely shouldn't be losing more weight.

Did the vet give her subcutaneous or IV fluids? Did he prescribe any medications? There are appetite stimulants that can be used, and a vet can show you how to give sub-q fluids at home. That would be easier and safer than forcing water, as there's always a risk of aspiration pneumonia. Is she on antibiotics? They can cause inappetance in some cats.

I second the tasty things idea.  She may also like some cooked chicken, or some grated hard cheese.  And she may like to be hand fed.  A bit of cream on the finger can get a few laps too  (don't worry, cream doesn't have lactose, nor does hard cheese, so she should be ok).  She'll probably like the tuna idea too - get the springwater version.  And then you can add a bit more tap water to moisten any portion that gets a bit dried out/get her to take more fluids. Again, a bit on your finger right under her nose might get the smell across that it is nice to eat.

Best wishes

She did literally lose half of her body weight and she has been eating 1 or 2 syringes every 3 hours (with exception of one 4 hour break when nobody is home). I've tried tuna and chicken and other yummy things but she just isn't interested. The doctor put her on another high calorie paste, a stimulating shot, and gave her a general antibiotic. She slept ALL night and seems to be feeling a little better... But she still won't eat on her own.

I'm so sorry to hear about your new baby. I too have a new kitten who is dealing with health issues. I'm afraid I don't have any advice that was not already mentioned, but just want to send you hugs and best wishes that your kitty bounces back quickly.