I often suffer from these bad memories from the past. My family all blamed me and I cannot see how they were my fault.

1. It was a school summer holiday and my parents were going to take us to a toy museum. I don't know which one but the TV and the radio had said it was good.
But my mum wanted all of us to have a bath before going. But I didn't feel like having one (please do not be too hard on me for this, have you ever not done something for not feeling like it?). So I decided not to go.
"You go. I'll stay here" I said, but I forgot my family had a stupid and unreasonable policy in response to this. They actually cancel the whole thing and blame it on me! They say I am spoiling it! How? I wasn't saying they couldn't go. I wanted them to go. It was my parents who were saying they couldn't go. Why couldn't my siblings blame them? I lay in my bad crying and I heard my sister say
"I hope you are satisfied Neil. You've made Nicola cry now".
I didn't reply but I wish I had shouted back "MUM AND DAD HAVE YOU MEAN!"
Eventually I heard my dad say "Come on let's get out of here" (but they went somewhere else) and my mum came to my room crying saying,
"Neil, why couldn't you have just come with us?"
My fault? I wasn't my decision to cancel the day out. Was there going to be a policeman outside saying "Where's Neil?"

2. I met this girl at college. She was a photography student. I met her while doing a work experience placement in the college.
She was always smiling at me and talking to me. She even introduced me to her friends. I was also impressed that she had won a photographic competition. But unfortunately I never got to offer her my friendship.
After I left the college my next work placement was near there. One day I walked past the college and there was the girl at the bus stop smiling at me. I offered her my friendship and she accepted but I didn't have a pen or paper with me. But I gave her my address.
I waited for her, she never came. So I waited out side the college for her and one day she came out with a boy with her. She said she came once and I wasn't in. I gave my address written down and the days I was in. "Oh thanks" she said. But she still never came.
So I wrote to her at the college as I didn't know her address and I didn't want her to lost out as I was really looking forward to this friendship. But she wrote back saying she was not interested in anymore friends.
I did not understand why. I tried to ask but the college wrote back to me telling to stop writing to her and also wrote a letter to my parents about it. They got angry and shouted at me. I told them I had heard enough. They were also angry about the fact I had got involved with the police to help a friend in trouble. "You don't get involved with the police" they said. If I was a kid I would have understood but I was 20. They even thought I could forget about his girl in one second, but the college had given her a
display in my home town.
I told them to shut up as I had heard enough but they wouldn't. It was impossible for me to stay. So I went to my grandparents. My nan kept telling me to go back home, all she could worry abut was my mum.
In my opinion my parents chucked me out as I had no intention to go out. But they said I left at free will.
So were these my fault?

In both cases it is at least partly your fault.

In the first case with your parents, they wanted your company. They were trying to please you by taking you out. The fact that you didn't want to go shows them that you did not wish to please them in return. They would feel upset and rejected by this, as they probably thought they were arranging it for your benefit and thought you would like it.

The second case with the girl is more straight forward. It was your fault, entirely. You gave her your address once and she didn't come to visit. Then you saw her with a boy, but you still gave it again. She still did not come to visit. How many times has she got to show you that she was not interested? She also wrote to tell you that she was not interested, but you still went after her. Why? What could she have done to show you even clearer that she didn't like you? There is no law that says she had to be friends with you just because you liked her. It is her right to choose whichever friends she wanted.

If someone likes you, they will always respond. If they don't, they will keep away from you. It is their right to like whom they wish. Learn when someone is NOT interested and then you will not cause problems with it. Accept when someone does not wish to progress a friendship. That is what sensible people do, otherwise you might be accused of harassing the person. Once you give a number or address to someone and they don't react, or ask for the information again, accept that as a NO and stop your attention.

It seems you need to work on your confidence and self esteem.