Is armor good at all? Advice?

So I have been playing this game for a while now. But I haven't really focused on any character until my marauder. I am lvl 49 and my friend and I have been dying a lot in cruel. Like to the point where we are considering not playing anymore. Its just too hard to get exp, and keep it.

So then I thought, well maybe I built him wrong. I focused on armor and resistances with some regen. Also, the synergies with iron reflexes and leather and steel boost armor ALOT.

I have Unwavering Stance, Iron reflexes, Leather and Steel, Trolls/golems blood, Blood drinker, 2x Diamond skin, and Berserking. I have a total of ~4200 defense with 61% reduc. In Cruel I have 60% fire, 47% cold, 47% lighting and 0% chaos res. I also only have 1050 life.

Now I already realize my life is low, so there isn't any need to go all "ZOMG WTF" here. I had the intention of not focusing on life as much from the start. But now that I am here, is it a useless build? Or is there some salvaging to do here?

Constructive criticism is the point. Thanks in advance.

Unfortunately having that minuscule amount of health will get you killed. Its mostly your build but maybe you could skin through till u get more SP, with better gear. then you could flesh out your health nodes. It would be very helpful if you linked your build and gear. Definitely link build though otherwise we really cant help you. We can only give a yes or no answer =D

What do you mean by SP
and how do I link my build? I mean like in screen shots?

Sorry SP = Skillpoint.
Posting builds hover over the games tab of PoE website and select passive tree. go down to drop-down menu and select mara and then transcribe your build into it. =D

http://www.pathofexile.com/passive-skill-tree/AAAAAgEAAdwFLQthDq0UIBjbG_ohAiFVIWAl3yi1KS4ppSr2MfsyCT38QKBDnFBQVbVYY18_YEtgiGEhYVJnm25pdO108XgNeWh673uMfLiE2YTvjM-euZ7Nn8ukGacwud2-ir6nwA_BBMbY0k3Uj9w94urvDu9O8i_2SPe-

That ability to post a build is very cool =D As for my equipment, is there some way to post it all too, or do I have to screen shot every one individually..?

Armor is only good if you combine it with other damage reduction mechanics.
Having a lot of armor will not make you unkillable. Having a lot of armor + endurance + enfeeble, might make you unkillable:
http://www.youtube.com/watch?v=lT9bmgduV3U

For items, just start a post and then press on your charactername on the top. Your stash is going to open up. Press on an item, and then close the stash. The item will be displayed in your post.
Like this:

The major flaw of your built is lack of Resolute technique, since you are not dex based nor crit character there are no downsides of getting it, it will also provide you more survivability as life gain on hit will provide you with more hp, also bloodrinker is pretty much useless at low level since you arent doing enough damage, id say your built is fine as it is, you should keep up endurance charges at all times and you should be doing fine. Also take a note that not having maxed resistances is really bad, you should always aim to have 75% resistances, except chaos ofcourse.

Alright, next step.
What skills/support gems do you use?
What weapon do you use as you can more efficient in speccing.

Armor is actually very useful, but you need, as you already know, a decent HP pool, and you also need to stack it appropriately.

That means you can't just wear some random assortment of stuff and take some armor nodes and call it a day.

You want high base armor pieces, armor nodes, grace aura + iron reflexes, and determination. When you combine all of that, armor is good. Combine with other reduction mechanics and leech on main skill and you can achieve insane reduction levels.