Am I wrong for leaving my girlfriend after she turned me down for my second proposal?

I (41M) have been dating my ex girlfriend (39F) for nearly Six years. Our relationship was a good one. Two years ago I informed her family and friends I was going to propose to her while we were on a family vacation and received their blessing and well-wishes. The night I proposed, I tried to make the night as memorable and "perfect" as possible. I asked her after a nice dinner surrounded by the family, and she said "No, not yet anyways." I was quite hurt honestly and went back to our room to think things out and not overreact.

A few hours later she came to the room and asked me what was wrong and why I left the group. We had a fairly long conversation as to my feelings and her reason to deny my proposal. Turns out she didn't think I was ready for the commitment just yet. So I took her thoughts to heart and informed her I understand her reasoning, however I was raised in a way where "you take a no for a no, not a maybe next time."

She asked me to just wait a bit longer until we were in a stable place, and I agreed. Eight to ten months later she started dropping hints that she was ready to be married "I can't wait for our wedding... Our wedding is going to be spectacular... I am so looking forward to my dad walking me down the aisle"... etc. A little over a year since my first proposal, I decided to propose again, this time just us together after a wonderful date night. When I opened the ring box, she got really quiet and once again said "No, not yet... maybe a little more down the line."

After this second refusal, I was done. It sounds cold, but it was the truth. When we got back home, I slept in our guest bedroom and spent the rest of the night thinking of our relationship. The next morning she asked why I didn't sleep with her in our bedroom, and I told her the truth, and informed her that I think we need to end the relationship. I informed her that I take marriage very seriously, and I do not want to be lead on and this time, this no was the final no.
Updates
7 mo
I gave her a month to find a new place to live, and since then I have been receiving texts and emails from her friends and family informing me I am a heartless bastard and trying to get me to give her more time, and not be a callous asshole. My friends have my back on this, and understand why I ended the relationship.
Am I wrong for leaving my girlfriend after she turned me down for my second proposal?
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