Can you just say those things? Like, 'I fully intend to honor this commitment and will do everything in my power to make this a good experience, but...'
'I need to know I can call and you won't give me crap when I have a bad day.'
'This is going to be really hard and I need to know you will understand that, empathize and give me encouragement.'
'I need to know I can lean on you emotionally sometimes. Not all the time, but when I really need it, will you be there for me? '
I wish you only the very best as you embrace this exciting/scary/wonderful new adventure....