Do you ever worry about being sectioned because you are alone?

For some years now I have been thinking will my siblings section me when my parents die. I even went to the doctor once about it and she laughed at me.

I had a few very bad years where I was emotionally compromised and nearly had a breakdown. I had been talking to people online in chat rooms and now look back and think they where screwing with my head and wanted to hurt me.
At one stage after chatting with them they called the police to my home. The police didn't appear to investigate or respond to me. To this day I still don't know who they where. When I attempted to get more information the police station they said they couldn't tell me who it was and that I would have to go through a solicitor. This was due to confidentiality.

I live with my parents and help run their business. They rely on me to help out. I also work full time in another job. I am single and don't have any close friends. I wouldn't call myself lonely or alone, more that I have come to prefer a more solitude life.
I do go out regularly for fitness and socialise when the opportunity arises but I am not active in the community in the way I am lead to believe everyone should be.

I don't have a good relationship with my brothers and sisters. Over the last few years it has declined further. Since my parents told my siblings of what they will inherit I feel as though they are bitter and spiteful towards me. I stopped responding to their requests such as sitting their kids and doing them favours. One of my siblings even accused me of fraud. When I called the police for advice they said they would ring me back and 15 minutes later they where at my home. I was very annoyed. It was almost as if they were in on trying to set me up. Oddly they left soon very shortly after I told them I had started recording all conversations that involve my family due to what I have to put up with.

I took advice from my doctor and councillor to limit my interactions and say no more. It has gotten to the stage where I have stopped speaking and interacting with them. I am starting to believe they where somehow behind the online abuse against me.
I found that they don't recognise that I have a life of my own and their life priorities are first over my own.

Now that I don't interact with them they appear to use that against me to make me look bad to anyone that is around.
I am often called a hermit and gas lighting nearly always occurs against me when I bring up an issue or concern or something important to me that would clash with them. I believe they also use their children as a front to intimidate me and make me look like a mean person even though I looked after them for most of their lives.

It feels that I am against a lot of people and that I can trust few.
I know I can move out and away but I want my own life and I don't see why I should change to suit people who give me nothing good for my life in return. Family or no family they made and still make their own choices.

There is more to the story. Bad and good but every time I go over it I still come to the same conclusion - that I want to be able to live my own life without having to always meet the expectations of everyone around me, and anything good and bad that happened in the past was me trying to achieve that.

My parents have acknowledged that I have my own life and have stopped hampering me in terms of my life's decisions but my siblings are like a persistent attack on my life.

How can I deal with this without running away or giving up?
Is this just normal life with siblings?

Well that sounds like a harsh situation.
Sadly, you can't control siblings, nor their reactions to you. Sometimes it's good, sometimes it's bad. Insofar from the situation you described, without knowing more than that, I agree with your approach, sadly, I might add, because it's always sad when cleavages like this happens in family.
The only thing I can warn you about, and this is not specifically pertaining to what you described but in general, is when we are very solitary, we do have a tendency sometimes to "paranoi" or see links where none might not necessarily exist. The part where they used their children against you reminded me of that. Which TOTALLY doesn't mean you're wrong, by the way, I don't know enough about the situation to really be able to accurately judge, but what I do mean is I would continue to focus on improving and making your own life as best you can, instead of wondering wether or not many are against you. In the end you should focus on you and the people that matter will recognize it for what it is, regardless of whom moves against you.
Trusting few is not necessarily a bad thing. I have always feared trusting many, simply because many aren't that worthy of trust in the first place, not by my definition of it at least. To me it goes with "chose your friends carefully" in that respect.

Besides that, I don't have much in the way of advice, I'm sorry. It's a sad situation and I'm sorry you're going through it, for what it's worth. Feel free to talk about it, or vent, as much as you want to in these forums.

As for wether it's normal or not...I have one sister and even though we used to be the best friends in the world, I dread the day when my folks day and money becomes an issue between us. For me it's never been much of a thing, but I wonder for her what it's going to look like...
So yeah, it might be. Depends on the people we allow ourselves to become.

Good day, my friend.