Concerns for welfare of my dad

My dad has been diagnosed with lung cancer, he told me in February but he's said things that suggest he knew long before he told me the news. He told me it wasn't aggressive and he'd get palliative chemo to extend his life expectancy. He then said that the tumor had grown a tail which has wrapped itself around his heart and there were no treatment options for him

When I went to visit him on the day he told me about his cancer, he broke the news to me that he had signed over his property to the woman who lives with him, it's not a romantic relationship they have now, they were in a relationship about 25 years ago but it became platonic and they continued to live together but leading separate lives. She is now the sole person on the title deeds and mortgage. 

I don't trust this lady at all. She claims to be my dad's carer but her care can be sporadic and if it doesn't fit in with her plans then there's no care at all. Last Christmas my dad had half of his foot amputated and she left him alone so she could spend Christmas with her own father, sadly it wasn't logistically possible for him to come to me on account of transport and access issues to my property but I did a meals on wheels Christmas lunch for him so I could check he was ok. My husband and daughter were struck down by the most hideous flu over Christmas so I couldn't really stop for long with him but I did my best to make sure he had a dinner and I was thinking of him.

Another reason for my lack of trust is because back in 2012 my dad became very unwell and I spent all weekend looking after him and calling out of hours docs and I also enlisted the help of my best friend who is a nurse. My friend said that the woman/housemate needed to get in touch with my dad's GP on Monday but she didn't, instead she left him with a pint of water and two slices of toast and went to work for her 12 hour shift leaving my dad alone. I tried to call my dad that morning and he answered but was completely delirious so I left work and rushed to his house. When I got there he was naked, rolling around in his own diarrhoea and completely out of it. I called his GP and when they arrived an ambulance was called. He was in kidney failure and had gangrene in his left foot. He was placed on dialysis until he was fit enough for the surgery to remove almost all of his left leg. The woman then started to say I wasn't allowed to help get his home ready for his discharge and asked me to stay away. I did as much as I could under the circumstances but it was difficult to make any difference when my presence was not welcomed.

My dad's mental health has been very volatile since his amputation and I have tried so many times to get him the help he needed but I was told that woman had it in hand. 

I got a call from my dad today, he said he was in hospital after having a fall from his wheelchair and he was being treated for the bruising. I did a four year stint as a domiciliary carer and I know the NHS doesn't keep you in for bruising. He couldn't tell me what ward he was in so on arriving at the hospital this evening I asked at the main reception. I was told he was in the cystic fibrosis ward which told me immediately that it was more than just bruises. By this point I'm quite upset because again he's not telling me the truth or giving me all the details. 

I asked the receptionist if she could tell me if I was still named as my dad's next of kin so I could speak to the doctor or nurses, she asked my name and I could tell by her face that I was no longer my dad's NOK. I knew she wouldn't be able to confirm if it was the woman that was now named but she didn't need to say anything, I knew. 

I went to my dad's room and his physical condition was a massive shock, my last visit with him was only a couple of weeks ago. He was painfully thin, drifting in and out of consciousness and still trying to feed me the line that it was just bruising he was in for. He then said he had received four lots of antibiotics but he was fine and there was nothing wrong with him. 

The woman hasn't been in touch with me to let me know my dad is this frail and in hospital. 

He really had the appearance of someone in the much later stages of cancer than he's telling me he is. 

I'm so upset and hurt, it feels like he doesn't want me to be there for him, he's feeding me all this information that doesn't match up with how he looks and I don't know if it's because he thinks he's protecting me or whether he just doesn't want me around. 

He started to get really defensive with me during this visit and suggested that because I don't call him (not true, I was always the one who called and made the effort) was a good enough reason to remove me as his NOK. 

I've taken the woman's phone number from him tonight and text her asking for a conversation with her to see if I can get anymore information from her about his condition but I haven't heard back from her yet. 

I'm worried that I'll not have the opportunity to spend time with my dad in his final hours because this woman won't tell me and the hospital won't inform me because I'm not nok anymore. I'll also not be a part of his funeral arrangements and that is hard to wrap my head around.

In his more lucid days he expressed the desire to have his ashes spread at a particular place and I'll have no way of doing that now that I'm not named as his NOK.

Do I have any rights at all regarding being informed by the hospital? I feel so helpless. 

The only other option I can see is to walk away and hope that I'll receive updates from this woman about my dad's condition and that doesn't sit well with me, I'm not sure I can do that. 

Don't know what I'm hoping to achieve with this post, just feeling lost and don't know where to look for answers