Their findings were that the ecstasy users were only 80% as good as controls at one specific task that involved memorizing words. I suggest you look at Cole 2005:
http://www.maps.org/sys/w3pb.pl?mode=search&c_pkey=22728&displayformat=allinfo&type=citation
They found something rather interesting: When they gave word memorization tests to ecstasy users who had been told that ecstasy caused memory problems, those users didn't perform as well as non-users. BUT, when they told a group of ecstasy users before the tests that ecstasy DID NOT harm memory, that group actually did better than the non- drug users.
It's become a sort of self-fulfilling prophesy. People's assumption (such as yours) that their past ecstasy use will have impaired their memory causes anxiety/stress that actually does impair their memory. Cool, huh?
But, let's just say for a moment that the work you cite can be trusted at face value. A 20% reduction in ability to memorize word lists. Is that really what you're hanging your hat on as an explanation for why you have recurring thoughts of killing yourself?
The NeXT studies also found small reductions in blood flow in the brains of ecstasy users. However, this is a well-known effect of transitory neuroadaptive changes in receptor density following exposure to MDMA. There is no reason to assume neurological injury on the basis of these findings.
And again, the chronology just doesn't work. Neurotoxicity (if it occurred) is an acute event, like breaking your leg. As numerous animal experiments have shown, it doesn't have a six month grace period before it takes effect.
I've seen horrible things caused by MDMA. Death, addition, mental illness, suffering of all sorts. I'm not some nutter that thinks this drug is all harmless sunshine and light, because it isn't. But the evidence simply does not support your conclusion that you've fried your brain with this drug.
The more direct measurements of brain injury in users simply aren't there, either.
It's a measurement of a particular protein that's found on serotonin axons (the parts in the brain that MDMA neurotoxicity would destroy.) There's a small reduction in current users (which is expected; the brain makes fewer of these proteins as a reaction to the drug exposure), but former users are back to normal (something that couldn't happen if there had been a significant structural loss of axons.)
Oh, and that group of ecstasy users? They averaged about 800 tablets. Not exactly light users.
So, when I say that you're wrong, I'm not pulling that assessment out of my ass; it's an opinion based on a high level of expertise and familiarity with a vast body of research in the field. I do know what I'm talking about.
So try to relax a little. As I've said before, it's incredibly unlikely that you're brain damaged. Screwed up in other ways by other means, yes, but nothing that therapy, soul-searching, and perhaps medication can't help. That's good news, I would say.