Oftentimes, they ignore it completely because they have no clue what to do about it. However, they could possibly not care also, we humans are self-centered at heart.
Possibly, that could be the way they feel loved themselves. Most people like hugging, though it's perfectly normal not to like it. If someone, especially a sibling, is making an effort to love you, they're probably going to hug you. However, they don't know you don't like it, but by your disliking their hugs, they may translate it as not wanting their love. It's all about the love language, sweetheart, everyone has one of the five:
Words of affirmation
Acts of service
Most of us who grew up love starved (aka, we don't feel very loved at home) Have a secondary way to feel loved. A major and a minor if you will. Since you don't like being hugged, physical touch probably isn't one of your love languages. However, by what you've said, I think Words of affirmation might be your major one.
One way to tell what your love language is is by feeling how people hurt you most. Does it hurt you emotionally more when people are cruel to you verbally, hit you physically, never give you gifts of any kind, never do anything for you, or never spend time with you? Which of those spells hate the boldest? Whichever one it is, that's the way you can also feel most loved.
Now, knowing your love language won't change the fact that you don't feel loved by other people. Fixing this isn't easy, or fun. However, one step in the right direction is to genuinely tell people how you feel when they hurt you. I know it makes you feel vulnerable, but sometimes, the only way to open ourselves to be loved is to risk being hated. Very few people who claim to be Christians will actively try to hurt you. If they discover they've hurt you, they'll feel ashamed and do their best to make it better. If they do keep pouring hate, that's blood on their hands, not yours.