<human>: We've been together 5 1/2 years, starting in University. We were each others first love, and I always saw us together forever - we were invincible. I was planning on proposing soon.

Yesterday, she ended things with me.

In my heart, I think it's because I wasn't a good enough person to her. On a macro-level, I was the perfect boyfriend; I always put her first, sacrificed for her, and fully supported her dreams. I never cheated, flirted, lied, yelled at her, put her down, was a dick, or made her feel unwanted in any way. I really did try hard in the relationship (I even gave up a dream job working in California for her); however I look back now and I see 1000 things I could have done better. The little things, like telling her she was beautiful more often instead of the more colloquial "looking good babe" variants.

I'm drowning in guilt and regret: that the reason the best thing to ever happen to me ended, and it was my fault.

I am afraid that this guilt will never go away, and that it's the price I must pay for letting her get away.

Can you summarize the given text in a few sentences?
<bot>: I feel I could have been have been a better boyfriend, now that its over, I wonder if that guilt will ever go away