D.P.
Ok, so my answer is going to be a little outside the box, and I am prepared for the onslaught of angry rebuttals... lol My son was the same way (colicky), and I was at my breaking point with the constant breastfeeding, screaming, poor sleeping, projectile spitup, repeat all day and night. My solution- supplement with formula for that last feeding before bedtime. When I did this, he slept through the night more consistenty- by sleeping through the night, he would sleep anywhere from 5-7 hours at a stretch. My husband would give him a bottle around 11 at night (while I slept- hoorah!) and that kept him way more settled through most of the night. Interestingly enough, after I started supplementing with formula, the colic started to get better, especially at night. We found out later that he had multiple food allergies (one of which was NOT dairy)- I would have never figured it out the right combination by watching my diet.
Anyway, it's just a thought. I know what it's like to have a colicky infant who sleeps poorly, breastfeed, and be the primary caregiver. It might be worth a try for your own sanity. If you are against it, then don't try it. I am not pushing it either way- I am just letting you know what worked for me.
Take care.