SHORT ANSWER
Keep contact and ordinary routines going, offer practical help without ultimatums, and protect your own health: support that burns you out stops being support. A person who is not ready to "treat right now" can still take small steps — together with you.
Why is that?
Why contact matters more than persuasion: isolation worsens most mental health conditions; regular ordinary activities (food, a walk, sleeping nearby) maintain the rhythm of life that breaks first in depression and anxiety. Persuading "correctly" is not your job; your job is to stay in contact until the person themselves is ready for a bigger step.
Why pressure harms: ultimatums and hours-long arguments about diagnosis are perceived as an attack and increase resistance; hiding medicines without a plan with the doctor is dangerous (abrupt withdrawal) and destroys trust — and trust is what all subsequent help is built on.
Why your own health matters: caregiving burden is real and measurable — burnout of a close person worsens both their state and the course of the condition of the one they are helping. Rest, your own people and, if needed, your own consultation — this is not selfishness but a condition for sustainable help.
WHAT TO DO
- You can: keep ordinary routines; offer to look up information or book together; talk about your feelings without blame ("I am tired, I need a break").
- Avoid: threatening to cut ties "if you don't go"; arguing hours about diagnosis; hiding medicines without a plan with the doctor.
- If safety is at risk — emergency services; in that case support means action, not waiting.