Ok one of the most important things when you speak with the surgery is to use the correct terminology. You need to tell them you are bed-bound and "unable to leave your bed/home even with assistance".
If a face-to-face visit is refused, you need to request a telephone consultation with the duty doctor that same morning. GPs are required to triage, and if they deem a visit unnecessary, they must offer a phone call or other consultation.
You also (as well as getting GP assessment, not instead of) need to ask the surgery about being referred to the district nursing team. They can help assess you for things like pressure sores, managing medication and general health checking.
Please do contact your local council for a care needs assessment to bring in external care support. You can find their details through Google.
You sound extremely vulnerable and you are entitled to health and social care for your needs. This current situation is no good! Especially with your partner being so ill too.
If the surgery still refuses a home visit (they won’t, if you use the right words), then it’s a formal complaint to the practice manager. Mumsnetters can help you draft something if you’re not able to do it or to use AI to draft.
You might also want to contact the Patient Advice and Liaison Service (PALS) - they can offer advice and assistance for issues with GP services. https://www.nhs.uk/service-search/other-health-services/patient-advice-and-liaison-services-pals/
Come on OP, we are all rooting for you - please, please call the surgery and local council today to get help. You can do it!