confused what to do

much needed advice

Hi guys, i apologise for the length but i need to say whats on my mind so firstly a bit of background about me.

I am in a dilemma. I realise my issues may seem small to most people but maybe I have a personality disorder. I do find simple things in life a lot harder than most people. I see people around me marrying and having children and getting good jobs and just knowing what it is they want in life. However, I am simply clueless and cant make a decision to save my life. Everything is a big ordeal for me and I have no direction in my life. I dont know where Im going or what I'm supposed to be doing. but for now, here is my current pressure and worry.

I am working in a bank for the past 10 months. it started as a 3 month contract and was extended 3 times so i am now in the 4th contract. I like the job, im content there and the people are nice and friendly. I feel like being in this job will help my cv in the future as before this i didnt have much experience in anything. I really like having money and keeping busy on one hand. On the other, I am finding the job mentally draining every ounce of me. The job involves typing figures into the database nonstop. There are literally thousands of sheets to be typed in and they never end. I have to complete all the sheets that are in for that day on the day. Obviously when its overloaded, the rest of the team will help me but every single day is hectic and I have non stop work. Its robotic and repetitive. My superviser sometimes praises me for being a star and working hard and i do feel good when i get praised. I find my eyes are so painful at the end of the day and I simply will fall asleep watching tv or looking at my phone. I guess I always feel the benefits out weigh the negatives.

Recently family issues and issues in my personal life have come to pressure me and I feel like I am losing all sense of organisation. My mind is cluttered constantly and I cant clear it out. But I am coping every day taking it day by day. I am suffering from health problems and am tired all the time. Anyway to get to my main problem. My parents are selling the house in the new year. I have a lot of stuff to sort out and no time to do it. I am afraid that with this job, the stresses will mount more and more when all my stuff is being moved. I know from the past that it is very difficult to get time off with this job. when i am not in, the rest of the team will suffer immensely so i really cant take any time off. my current contract ends in november and the way things are looking will be extended continuously, maybe i will even be given a longer contract after that.
I just feel very stressed with all the things in my mind that I feel I should take a bit of time off in the new year and move wherever im going and settle in without feeling guilty or having the stress of work or the tiredness of work on top of everything. i feel i will be better returning to work then with a better clearer mind. am i right? also in the time i am off i can act as carer for my grandmother. so to do this, i would need to give plenty of notice to work. perhaps i should tell them in november or december that from january onwards i wont be working. how should i go about it though? i want to be professional and would love to return to them in the future after a few weeks or months. what could i say to my manager that would allow me to possibly return when my life is a bit more organised? money wont be an issue for me for a little while as i have a bit saved. should i tell my manager i wish to leave the job at the end of the current contract or that i wish to leave in january or how should i go about it? if i do this, am i closing this door forever? could i simply say "i have no idea if my contract will be extended or not but just to let you know i will be leaving the job at the end of the year as i have a relative to take care of. i would love to return to you after a few weeks or months but i am aware this may not be possible." can anybody help? thank you for your patience