My female cat refuses to feed her newborn kittens and i would feel guilty if they were to die,what can i do?:(?

I have a female cat who gave birth 2 weeks ago...She had five kittens, three already died (died instantly) and i'm trying very hard to save the last two! They are very badly nourished and i think another one is about to die today..I took them to a vet and he told me there was not much to do but buy kitten formula from petco or any other pet store, or to make a homemade kitty formula for the kittens to take for the first day,and see how they react and then if they show positive signs to go ahead and buy the vitamized kitty formula from a pet store. He gave me the recipe to this home-made formula( 8oz homogenized milk,2 egg yolks,one teaspoon of salad oil and one drop liquid pediatric vitamins (optional). He told me to keep them in a very warm environment.To fix a basket with plenty of warm blankets etc..P.s They don't like it there.. And my female cat detests them and refuses to breast feed them,( I'm so sad i don't want the kittens to die)..But the vet does not give me much hope.He said it's like a 50/50 chance of survival. The kittens seem to stop crying when they sleep beside me or i cuddle them to sleep..So for now i'm basically not sleeping at all! i'm just watching over them since they are sleeping with me for now..I'm basically playing mother and they look so fragile,sweet,and innocent...Idk i just can't think of them perishing.It would give me a really bad input, as i'm trying really hard to save them... I'm trying everything that's within my ability to help these kittens..i took them to a vet, i'm feeding them 33cc or 1.1 oz kitten formula per day 9 to 12 times a day, I keep them warm , clean them with baby wipes etc.. I'm really trying my extreme best to save atleast one! Please help! is there anything you may suggest as an extra advice to increase the chances of them surviving:( I would so much appreciate your caring advice! thnx