Giving up PIP

Hello there,
Is there anyone who can advise me please on PIP. I’ve getting PIP for just over a year. Whilst my health conditions haven’t really changed in fact I’m due for a CT scan on my heart in April as I have palpitations and I’ve been put in beta blockers this month. I’ve also been tested to see if I might have ADHD bout 4 weeks ago I think. Naturally it looks highly likely I am… but I’ve said I don’t want another diagnosis and another pill to take so for now I’m not going further with the ADHD. What has changed is my mood has lightened, I can’t say it’s all the time as I’m worried sick about the CY scan and I am trying to get out of the house a bit more than usual. Problem is because of fibromyalgia and my thyroid if I exert myself one day then I’m out of it for at least 3-4 days to recover. I’ve never had exhaustion like this in my life before.
Perversely my depression has lifted mainly because the heart consultant was so horrid and patronising and said he won’t allow my CT scan if I didn’t take my medication, I felt so small and was so scared and my anxiety levels hit the roof. But a few days after I just thought I’ve had enough. I’m 57 and was spoken to like a child by a person probably 20 years younger than me.
Aldo my financial circumstances have changed, my lovely father left me some money in his will. So no longer claiming PIP wouldn’t be based on any health changes except for the depression lifting slightly but purely my financial change. I read on the gov website PIP is not given based on income or a change in money but I just feel for me personally, it’s the right thing to do. So my question is how do I tell the DWP? I’ve searched on Google and some answers are just a bit scary and people have written that don’t say too much just say you want to voluntarily give up PIP but my son said what if they ask exactly why and as my sister and I didn’t get the money till Feb they might ask why I didn’t give up sooner but I was still so low then and couldn’t think straight. I’m so scared of getting into trouble, I only started PIP because I couldn’t work anymore I was in physical pain and my mental health was dreadful so we were really struggling. My father lived with us full time till he died and used to pay his share of the rent and everything just got on top of me. Sorry this is so long but I want to have all the facts before I ask for advice. Thank you I’m advance for any help

Amy, I’d feel exactly the same if I was in your shoes. I too have experienced them saying I refuse to take my pills … like I’m a bad dog or something 🙄 I’ve had a fair few arguments with them too, so no longer feel there’s any point seeing any of the Dr’s at my surgery. But you could hang on to the PIP for the time being, & just don’t bother to fill the forms in when you next come up for assessment.