Why can't my mom trust me?

So I'm going through a lot right now and I told my mom my frustrations. She made it worse by questioning me about my step dad and if he's touched me. She looked through my phone and asked why I called him and it's mainly me calling her because she left her phone. It's like she's accusing me of doing inappropriate things with him. Saying "why are you calling him? What'd you two talk about?" It's stressful she even recorded stuff to see if she'll catch anything. I keep telling her that nothing happened. I can't help she can't trust my step dad but I'm tired of her coming at me about it and questioning me. I told her I'm not about to get questioned anymore. She's all like "you're not the only one going through hell, you seriously got mad because I asked about him?" It's not just asking it's going through my phone, waking me up at night threatening to take me to my brother's house if I'm lying, asking me if he's touched me. She apologized but I need to leave from here.
Why can't my mom trust me?
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