What's the difference between "ashamed", "shamed", and "shameful"?

Native speaker’s answer
Rebecca
"Ashamed" and "shameful" are both adjectives. "Ashamed" means to be embarrassed or guilty of one's actions, characteristics, or thoughts. For something to be "shameful," it is unacceptable and causes shame or disgrace. To be "shamed" is a verb, which means to try and make someone ashamed or to humiliate them for something. Ex: I felt shamed by my family when I told them I was dropping out of med school. Ex: She was ashamed of her grades and knew she could have done better. Ex: Your actions of missing the party and sneaking out are shameful. You need to apologise to the host now.