No matter what, keep in mind that many are thinking of you and sympathize to the fullest (and that goes for others on the forum and their friends and family in the midst of their challenges) as well as offering prayers for you and yours. I've had those helpless feelings too in the last little while; Dad passed two weeks ago. For my part, I can only point to in the direction that helped me -- to "the God of all comfort; Who comforts us in all our tribulation..." (from part of 2 Corinthians 1: 3-4). Turning to God and not away from God when at the worst of pain, despair, and helplessness was and is the key, I firmly believe.
There were so many challenges and "new normals" that came up as the end neared that my head was spinning and my heart was broken (which comes with the territory regardless), but I needed help and strength, and I asked God for help, strength and guidance. I can't tell you how many times I felt I was facing a wall but found a way to proceed that helped me cope with what was being presented, if it meant being strong for another family member or for helping deal with logistical challenges and finding ways to make sure his caregivers were getting Dad whatever was needed at a particular time.
Draw close to those who are care and are willing to offer you support in this time. That includes so many on this board who have been so generous with their kind words of encouragement, guidance, and consolation. All the best.