Can my parents read my texts?

[Ben]

Last night my parents were telling me about how they knew that i went to a party last weekend and when i asked them how they found out they responded with "we hear things". My parents are always checking my social media and know the passwords to everything. The only way they could of found out is by reading my text messages. Can they do this?? and if so how?? I feel like I should have some privacy in my life.