Mountains vs Me

My boyfriend's brother LOVES climbing mountains with gis girlfriend. My boyfriend with the influence of his brother which he idolizes alot, wants to climb too but the thing is, I HAVE A HEART AILMENT AND I CAN'T GO WITH HIM.  I asked him to travel the world with me, check all the cool places around the world, the beaches, etc. instead of climbing mountains but he chose to climb.. And right now. I dont really know what to do.