Stephen and I started dating on March 25th of 2011. We moved in together that August and we've been talking about getting married since. It's all been in hypotheticals - the fun part of wedding planning before you're actually committed to the whole thing. I've had no doubts that I want to spend the rest of my life with him and honestly, I was starting to get impatient about being officially engaged!
In August, we took a two week vacation to visit his parents in Ireland and during that trip, we went to London for a weekend to visit his sister and her family. I had a feeling he was going to propose at some point during the trip but as we were nearing the end of our weekend in London, I put it aside and knew he'd ask when he was good and ready.
We crammed a lot of sight-seeing into that weekend - a bus tour all over central London, a ride on the London Eye, a walk through Hyde Park and a visit to Buckingham Palace. Finally, on Sunday afternoon, we took a break in Kensington Gardens, the site of Kensington Palace where Princess Diana made her home. It was a great day - not too warm, lots of people out and about because the next Monday was a bank holiday, etc.
We sat in the grass by the Round Pond and watched children feed the birds (so many swans!) and just relaxed and enjoyed the day. As we were leaving, Stephen spotted an empty bench next to the pond, directly opposite the palace. I wasn't sure why he was so excited about the bench, since we were leaving but hey, I like to sit on benches.
I'm not sure how long we were sitting there before he said "I've had a lot of happy memories in this place" and reached into his pocket. "I hope this will be the happiest memory of them all" and pulled a ring box from his pocket.
I will freely admit that I was completely overwhelmed and said "Oh my god what are you doing right now??" He even got down on one knee! There was crying and hugging and I said yes, obviously. Here's a picture I made him take with me right after.

So yup, we're engaged and I am such a happy, lucky girl. We haven't set a date or started any official planning - we're still enjoying the fun of being newly engaged.