He's ready 2 take the next step I'm not what should I do?

I just got out of a marriage that lasted 21 yrs because of what happen I have trust issues, My boyfriend of 8 months keeps hinting about being engaged & living 2 gether but I told him im not ready I just got out of a marriage of 21 yrs & don't want 2 make another mistake I love my boyfriend like i've never loved any 1 b4 he loves me & we think so much alike hes perfect 2 me & our relationship is almost perfect he understands me like no 1 I know. Im scared if I keep pushing him off he'll get tired of waiting? But I love him & know I really, really wanna be with him, he is my best friend. I just don't know what im waiting for? I get scared when I think of taking the next step & i don't know y? oh yeah I have 3 kids I haven't let him meet cause I dunno if Im ready for that either, yes he knows all about them & seen pictures. Whats wrong with me? & what am I waiting for? I will be 34 this year & hes 30.