A phrase uttered after saying something for which it fits, as judged by the speaker (usually it is said after mistakenly uttering a phrase that you know will come across as nostalgic in some way, often starting with the words "I used to..."). Alternatively, can be "BTA," "since the accident," or "STA." Usually accompanied by a stoic, nostalgic, headtilt when said in person.
I used to like Colbert... before the accident.
What's up with 3pac?
She's always been that way... since the accident.