Why do I feel disgusting when people tell me they love me?

[Hurleyclan5]

Whenever my parents tell me they love me or my sisters I feel embarrassed and I hate saying it back and with my gf I feel sick in my stomach also which happens when she compliments how I look idk why it’s either embarrassment/shame or smth like disgust idk how to describe it maybe unworthy of it? It doesn’t make sense