It's nice to see you've improved your equipment and attitude since the
VoD fiasco.
You're just barely able to do Abbot as you currently are. Like mentioned above, it's easy to fail, and without training and a good reputation, it's not easy to get into many of the LFM's. This applies to Sarlona, but I'm sure it applies to your server as well. Training tends to happen in guild/private groups, so you will rarely have a chance to do it normally via PUG'ing.
In addition, the Abbot is a caster, and you need to be able to survive some massive damage coming your way. Yes, you have evasion, which will help a good deal in keeping you alive. However, he also spews Disintegrates and Horrid Wilting around like mad. Those can't be evaded, and while you have a reasonable fort save, it's still not enough to save on everything besides rolling a 1. His Disintegrates can hit for 350 or so damage, which can mean death after a failed save on lightning bolt, chain lightning, meteor swarm, delayed blast fireball, getting hit by a Quell, and so on.
Abbot is also a raid where people are spread out so much that it's difficult to heal. One of the divine casters may also be on wand/inferno duty, so they're less likely to be able to heal everyone in the room. It's a raid where you should be able to take at least partial care of yourself. You're a ranger, use an Ardor clickie, get some healing amp, and heal yourself if the divine casters aren't able to get to you on time.
As a ranged ranger, you're not going to be breaking his DR, and even with greater undead bane arrows, you're not going to be doing a lot. His DR is around 20/Bludgeon, maybe more on elite, so most divines are going to be concentrating on the ones actually doing damage to the Abbot, or simply healing the Abbot and any melee around him. Casters are DPS in this raid. You're better off grabbing a pair of Holy/Undead Bane maces, warhammers, or morningstars and melee'ing him, or tossing the Asteroids at the Abbot than "pew-pew'ing" him (outside of Manyshot of course). He's also immune to Lightning, so leave your LitII (if you've made it yet) in your bag.
From MyDDO, you started with a 12 con, which is low (especially on a Drow) but not dangerously low. Your tome you said you used made a big difference, as well as getting equipment to compensate. Keep gathering equipment, and you'll be a lot more survivable.