NEED Help! getting no help from family and am the sole caregiver to grandparents! Cant do this alone!?

their four sons dont want to take responsibility but they dont mind letting the 18 year old grandkid do everything..Apart from the home health people coming out to give them baths....Im on call 24 hours a day between the grandparetns...but I have to eventually get another job (was laid off and trying to look for a job..still looking and trying to juggle gpa in the hospital im the one who has to come up here everyday to tag a doctor down as well as manage to juggle taking care of my grandmother back at the house) ....and want to go to school...but everyone in the family refuses to help...they dont want to upset mommy and daddy...but what im seein is that they need a lot better care than what they have been getting...and if i could afford it would hire someone to sit with them to give me a break! doesnt matter if its 8am 8pm 2pm or 2 am guess whos up helping one of them get out of the bed or go to the bathroom...heck this is the second time and second week my gpa has been in the hospital...I CANNOT HANDLE THIS BY MYSELF~! is there anything that i can do? the rehab ppl who are reviewing his case are basically saying he needs rehab but of course gpa has the option to go home....he can hardly walk.. turning in the bed is a chore and today they are going to put 2 stints in his kidneys...um did i mention if he goes home he is going to soley depend on me! to do EVERYTHING! what if he falls AGAIN! Im not a nurse! As much as I want them to be happy I want what is best for them.... Right now im stuck being the bad guy becasue I want him and even my gma who could use the therapy and make her worry a lot less...(Shes prone to blood clots and she's a worry wort...which means she can become a bit well bickery and guess who gets the whirlwind of emotins) go to the rehab center. because of bad instences with other gparents in nursing homes we are using that as the absolute last resort...SO IS THERE ANYTHING ELSE THAT I CAN DO!!!! could i get power of attorney or something to get them help? im too young to have to be making these decisions or to know really what to do especailly regaurding other peoples futures! but it looks like im the only one who will become the bad guy to get them help! Everyone thinks because ive been here that ill stay here no matter what...and no body has to lift a finger cause someone else is taking up their responsibility..HOW CAN I GET THEIR SONS TO GROW SOME AND HELP!!!! I CANT DO THIS WITHOUT HELP!!