Am I a selfish Christian or selfish sister?

I work as admin assistant at hospital and my salary is minimum wage and my older sister (Jo) has huge debt like about 50k pesos. My salary is on day 25th and she always text me asking me if she could borrow some money because she's struggling but all I know is that when she borrows money from me she will just use it to pay the money she owe from different people. I told her I will buy a new mattress on my next salary and she always text me constantly asking me to lend her money so I told her on day 25th I will lend her money for about 1k pesos. by the way my sister (Jo) has working husband who is tig welder who has better salary than me her husband doesn't know my sister is in huge debt based on what I've heard from another sister ( Charry) Day 25th arrived and I bought a new matress which is expensive that I expected I bought groceries and paid utilities. I live with another sister in same house and she told me she can't pay water bill Im shocked because what Im gonna do if I go to work without taking a bath? And my only money left is 1k pesos and the water bill is 1200 pesos which is about same amount my sister I told my sister Im so broke right now and can't even lend her money right now because I need to pay water bill my sister Jo got mad cuz I promised her I will lend her money and she told me" why are you like that? I thought you will lend me money Im so broke right now? I will remember this day and I won't be asking any help from you. You know I need to pay my debt to this ASA (lending company) which sounds like she's guilting me to lend her money I explained I also have to pay water bill and need to pay today because it will be cut off tomorrow due date It will be hard for me to shower to go to work she still proceed to let her borrow money because she need it meaning she doesn't understand my situation but she just thinks her own situation despite explaining the water bill need to be paid today because due date is tomorrow. Am I bad sister?
Am I a selfish Christian or selfish sister?
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