The problem is that those emotions have built up over many many lifetimes, which is why they're so powerful right now.
First, try to pull out the ego's underpinnings regarding these negative emotions -- what kind of payoff or "juice" are you getting from it? It seems like we wouldn't get any payoff from such "negative" emotions, but we all know people who hang on to suffering, to negativity, to victimhood, etc. The payoff of feeling like a victim, or a martyr, or self-pity, or the payoff of hating negativity or hating the "bad" part of you (which just propagates the negativity), the pride of being "superior" by criticizing negativity, the attention that you get from others, etc. Be brutally honest and analyze yourself, find out all the payoffs you're getting, and be willing to surrender and let them go. Refuse to experience the pleasure of these ego payoffs. For me, I feel this emotional and mental clingingness that the ego wants to pull you into holding on to the current feeling, and I just try to unclench and let it go, over and over again, until it disappears.
After surrendering the ego payoffs, you're in a better situation to work with the emotions themselves. You've "unplugged" the cycle and you're not keeping it running, so to speak. However, the momentum is still pretty formidable and has built up through many lifetimes, and you've just got to keep running it out until it comes to a stop by itself. Sit with these negative emotions, and just experience them out. Don't juice it or fight it, just don't resist, be ok with it, be bored with it, and let it run.
You're right in that after these outbursts, it temporarily drags you down to a lower LOC and everything you see from that perspective will keep you stuck there. It seems like you already know how to cope with these situations and get yourself out, so the main thing is to just keep working with them. What I would do, is to proactively seek the things that trigger these negative emotions. Mentally think of the situations that cause negative emotional reactions, and experience and accept those emotions, but stay detached and clear from it, and keep surrendering it. Every situation then becomes an opportunity to let go of more and more of that negative emotional energy.
I highly recommend the Sedona Method, which is where I got the above technique from:
The Power of Letting Go - A Sample of How the Sedona Method Works
If it helps, I suggest getting the Sedona Method
book. It elaborates a lot more on the process, as well as many potential problem areas to proactively work on.