I cannot imagine how you are feeling, but please know that you are in my thoughts. Colic is so very horrendous, and having experienced the colic surgery first hand in December I know how quickly things can change.
All I can add is that time is a healer and eventually, your happy memories you shared with Squeak will over ride the sad memories of losing him.
I am so so sorry. At least he didn't suffer for long and you did what had to be done. Reminds me that we must appreciate our horses every day - one never knows what's just around the corner. Poor Squeak and poor you.
Such a loss.
Really Don't know what to say, Thoughts are with you,
Let the memories always live on.
RIP Squeak, a horse who will be very sadly missed as admired by so many xxxx