What do I do bc I’m too chicken to decide

So my neighbors brother, he’s 26 & I’m 21, have been like a thing but not a thing for a year... we hang out and have sex. At the beginning of this we contemplated dating but decided it wasn’t a good time with him finishing school, my dad had just passed away and our families are really close. Well fast forward 9 months and he gets pissy bc I started talking to someone from school (that lasted less than a month) and his demeanor toward me changes. He’s more affectionate, asks me to come over uses his nieces as an excuse to be around me sometimes( like if he knows I’m at his sisters he will come over), he now cuddles me before AND after sex. Both of our families know that there are feelings there but neither of us have brought up the dating topic again. Like I wish I could share every detail so that you could have better insight. He’s so awesome. He finishes school in 6 months. Should I wait it out and see if things change when he graduates or hope he expresses his undying love for me like in the movies.

Can I just add that every time his mom asks about us he tells her we are just friends but if she tries to set him up with someone he find the smallest thing wrong with them.