Meadow, it is really painful at first and that's completely normal. Try to avoid ruminating too much and don't panic.
You feel awful right now but it will get better, tomorrow will be better then the next day.
Few things that might help. Put the focus on yourself and look after yourself.
A good acronym is HALT - Hunger, Anger, Loneliness, and Tiredness. Keep these things in mind and avoid them, , make sure you eat and eat well, if you are tired, sleep, need to talk, post here or call a friend etc.
Second thing is, distraction. Early on distraction is your friend. Watch a movie, even a dumb movie, as long as it is slightly entertaining. Binge watch something on netflix, teach yourself how to knit.
Read the stickies at the top of the forum, there are hundreds of articles.
Most importantly, keep in mind why you are doing this. You are not to be abused. You are important and significant and you deserve to be treated well. Love isn't supposed to be so painful. As long as you were with this abusive man you were going to be hurt/angry/sad.
You will have another relationship, you now know about some more red flags to look out for.
In the meantime, as I said above, you won't always feel this way.