Communicate:
1. Tell them they can trust you and that you want to help.
2. Ask if they are talking to an adult and if they aren't, find a trusted adult they can talk to.
Offer Help:
1. Offer to go to the counselor's office with them.
2. Ask them if they want to go out to get their mind off of things.
Follow Through:
1. Ask maybe the next week how they're feeling and how you can be helping.
2. Ask the counselor of adult they're seeing if they are getting better.
This is a slap on the forehead obvious answer but, obviously contact a poison control center.
This could be because they understand their frustrations, or it could be you have not been loyal to them thats why they treat you this way.
Answer:
GET OUT OF THERE ASAP! If you don't consent and they continue to pressure, that's not a good person and they don't deserve any politeness from you. Tell them no and leave. Start voice recording on your phone so you have proof if anything happens.