Over the past year or so, a couple about 20 years older than me have been very kind to me. Due to all their help and support, I have really grown as a person. I will never be able to pay them back, and although I've always tried to emphasise how appreciative I am each time they have done something for me, I would like to write a thank you card which specifically explains why I'm grateful. But obviously that means being vulnerable and explaining the impact they've had on me, which isn't something I'm great at, though I'm improving. Would it be okay to go beyond "surface level" stuff and explain what I'm thankful for? I don't want to make things awkward or for either party to feel embarrassed. But I just want them to know that I don't take what they've done for me for granted and to encourage them as they've encouraged me.