You just found out that someone you care about has just received a medical diagnosis and you don't know what to say. You are not alone. This is a common feeling and it is ok to not always know what to do or say. What is important is to try to not react in speech or action without thinking sensitively first. Here are some ways to react that your loved one may appreciate.
1. Assume Nothing, Ask a Question:
You have no idea how your loved one feels, and making any assumptions about your loved one's experience may just lead to your loved one feeling misunderstood or alone. It is more helpful to simply ask, "how are you feeling?" than to state something like, "you must be so scared." You may be surprised by your loved one's answer. Some people are relieved to receive a diagnosis and know what has been ailing them for so long, others might feel angry or terrified. You do not know, so simply ask, which demonstrates a desire to listen and be present to your loved one.
2. Remember the Diagnosis is about Them Not About You:
Of course you will feel a number of your own emotions related to finding out about your loved one's diagnosis; however, you do not want your reaction to be about you. Your loved one already has enough to deal with and you don't want them spending their time trying to comfort you during a period where they need to be supported. Try giving your loved one a soft hug and ask them what they need from you. This will be much more helpful than falling apart.
3. Offer to Accompany Your Loved One to their Next Doctor's Appointment:
Receiving a medical diagnosis can feel like an isolating experience or like a burden one must walk with alone. Sometimes accompanying a loved one to a Doctor's appointment, or to a treatment or procedure can be extremely comforting. Simply ask your loved one if they would like you to join them but do not insist if they say "no." You can just tell them that they are free to tell you if they change their mind in the future.
4. Remain Aware that Your Loved One is In Control Of the Situation Not You:
So much is out of your loved one's control with respect to their health, so it is really important to let them have the lead in making their treatment decisions (assuming they are not a minor or lack capacity to make decisions). You may not always agree with their treatment choices, but it is their body and their choices to make. If you are really concerned that they are making the wrong decisions, non-judgmentally share your reasons for disagreeing and try to have an open dialogue about it, but be respectful of your loved one's right to some control during this chaotic and unpredictable time.