My rat of 2 years is going to be euthenised tommorow. should I do it?

My white albino rat, Orin, (named after the Baldurs Gate 3 character} has a large mamary tumor, that she has scratched at, causing it to rupture, and giving her a large wound. I and my family cannot afford surgery for her, let alone an appointment with the vet. ($75-80 for a checkup, $300 onwards for a surgery. They make you pay for the consultation before they get surgery if they need it.) She has bled out 4-5 times, all concerning amounts. Shes become anemic twice, despite my best efforts to cover the wound, and stop the bleeding. no matter what we try, a cone, wrapping her, plasters, everything. Her fur is loose and shes becoming patchy, and the tumor is almost bald, yet shes still upbeat, eating, snatching food and drinking. Since I am 16, I have school and responsibilities, and its horrific to me to keep coming home to find her in her own blood. she bled out twice today, shes fine active and happy, but i just cant take it anymore. a friend of mine has offered to pay for her euthinization. ($90) I love my girl, and I dont want her dying in pain alone in her box, but i also dont want her to be put down when she had a chance to like even a little longer. What do i do?