Am I Pressuring Him?

My boyfriend & have been together for 4.5 years, lived together for 2, I have 2 children from a previous relationship but only one of them lives with us. We had a trying start to our relationship (no cheating just stressful to say the least), but now we're both extremely happy, happier than we've been in our entire relationship-except about the future. He'll say "we" about everything-"our" house, kids, etc. but if I talk about "being excited" about marriage, a kid, starting his own business, he gets stressed and says I'm pressuring him. I don't insist about when we're getting married and I haven't given him a definitive timeline of when he needs to propose, I'm happy with where and what we have in life, but any woman would get excited about being married and having a child of our own. Talking to him about it is marriage is "someday", kids are "within a year or two". He wants to eventually start his own company, but when I mention I'm excited about that he scowls & says I'm pressuring him...I'm so confused! I guess I just don't know if he's a commitment phobe from seeing his parents terrible relationship, if he's waiting for the right moment, or if he's just enjoying the ride of playing "house" without a solid commitment. He's said if I didn't already have kids, and an ex-husband that he "has to deal with", we'd already be married (which makes me feel terrible for feeling restricted by things I can't change now), but it also feels like a cop-out...

Some insight to a male mind would be nice-Thanks :)
Am I Pressuring Him?
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