This is an excellent resource for cancer caregivers and survivors, one on one support available, peer mentorships/angels available: https://imermanangels.org/
Another organization that provides extensive resources for caregivers, not cancer specific: https://www.caregiver.org/
Aftercancer is a non-profit organization committed to providing educational resources to oncology care teams on integrating sexual health services for patients impacted by cancer. Sexual Health Resources for Those Affected by Cancer