I feel heartbroken.

My fiancé and I are 32, and 41. We’ve been together for a little over 6 years, and engaged for 2 and a half. We have a life together and live together. He won’t even buy me an engagement ring. He’s promised to ever since he asked me to marry him, but he never has. I’ve set myself up for a broken heart several holidays thinking “this is it”, and then it never is. I’ve asked him about it, and he always says “I will”, or “I’m gonna get you a ring, baby”. I always ask when and he’ll say “when you least expect it”. I can’t help but feel anger and resentment towards him. and it’s not just about the ring, but the promise behind it. I just feel like 6 years is a long time, and I feel like I shouldn’t be begging him to keep a promise to me. I’m not a materialistic person, and I don’t expect or want a big fancy rock..Our finances are fine and we have very little dept, so, in my mind, he just doesn’t want to move forward and onto the next step..and yes, I have talked to him about all of this and he just continues to make the same promises. I’m seriously contemplating moving out.