Why am I so fearful to move forward with my boyfriend??

I have tried to approach my boyfriend so many times to let him know I cannot live with him and/or we should break up (since I know he wants to live and marry me next year) after several years of dating.

My heart is still so attached to him...I do love him.

But...my head is telling me I'm making a really big mistake because we are just not financially compatible at all and we are both much older - i.e., I may end having to take care of him.

Every time I think I can do it; I "chicken out" after being with him for even an hour and sometimes, when I believe I've caught him in another financial lie (that has led to us breaking up in the past), it turns out he ends up telling me the "truth" or enough that breaking up with him at that point would seem crazy.

I know I don't need to "justify" breaking it off but he does give me a lot of emotional support - although my anxiety about his difficult financial situation also is not good for me.

I can also sense he is pushing me to move to the next step - for example, he keeps pushing me to put our photos on Facebook together but I almost never use Facebook and prefer to be a private person. He tells me he is anxious about us moving forward - I assume because he knows me well and can sense my hesitation.

In this just a case of being in different places? Push and pull - he wants to move to the next step and I cannot do that even though I love him, but because of practical reasons? I don't believe the passage of more time will help since we've been together almost 6 years and I have always been hesitant about living with him/marrying him.

What should I do?