Well, I don't like to turn down people, but I do if I know (or feel) I have nothing to offer.

"I love you" I find it hard to say as well and like you I have fingers left (on that 1 single hand. I wonder if it's easier to say to an animal? Perhaps, they don't expect you to give them the moon and stars? To always be present and give everything away?
People can be very exhausting, but dear.. being the rest of your life single and handsome I don't know. You can also have friend who appreciate, like and love you and have a good life.

Unlike you I didn't have a nice mom and my dad left as I was 11 with the words "take good care of your mother", the woman He couldn't take care of. Kind of strange thing to say. So no, I don't have an example of a loving home, not even a safe one, still it must be possible to connect to some, to reach out since if you don't people slowly forget you (great if that is what you want).

Life is long, extremely long if you have no one to visit Ikea with.

Most of us don't have good experiences and if you ask me it won't get any better since we all do as we like and we have no social skills, are not willing to listen a few minutes to another.

In short: You take revenge because of your sister, and those few who let you down, attract women and turn them down?
Read back what you wrote.

Well.. it's your life and if you like or not I like you!