Help making a Blood Magic based Tank- Blood Death Knight Theme

Hey fellas, thanks in advance for help. I am a newcomer to this game and would love to get started with my favorite playstyle without horribly butchering the character build. I love playing as a death knight/unholy paladin/reaver, where I utilize my HP as a resource pool and self-heal through life leech and what-not. Furthermore, I like to be obscenely tanky (synergizing the HP resource pool with a lot of HP and the life leech with resistances to bolster the effective value of the health stolen). Obviously this comes at the opportunity cost of sacrificing damage, which I am perfectly okay with. Still, getting some extra dps where it does not require a huge detour from defense is sometimes worth it. Is a viable build around this concept possible in this game?

I am assuming marauder would be the best class for it, point me in the right direction if I am somehow wrong on that. Other than that, sword and board seems the way to go to ensure I am tanky as possible. If a shield does not drastically increase tankiness in this game as it does in other rpg's, or at least enough to overcome the increase in life-leech from a dps increase by going with 2h weapons or something, let me know.

I am mostly concerned about the passive skill tree, as I am pretty anal about min/maxing, and this appears to be the only place where I could make a permanent, irreversible error in building my toon.

Looking through the tree, I am intrigued by blood magic (would seem to be the crux of this theme). Synergizing this with a giant hp pool would mean limitless ability spam with little worry about losing too much hp, I presume. Vaal pact fits the theme and would be cool were it not for the loss of hp regen. It seems better for a more damage oriented toon. Correct me if I am wrong. Unwavering stance also looks pretty incredible, given that I'll be a tank. Other than that, nothing really sticks out at me as fitting with the theme or supplementing it, other than the countless minor tanky nodes giving armor,hp life leech, regen and other defensive bonuses.

Be brutally honest with me! If blood magic sucks or is meant for something other than tanks, I'd rather find out now than countless hours into a useless toon.

Finally, if there is a well-regarded build that fits this theme already out there, please link it :) I had trouble finding one (which probably has bad implications lol).

Don't use BM - it might seem dandy to not worry about mana at all but as you progress you will want to use Auras and you cant with BM. Vaals pact also cannot be used with BM. If you want to build tanky I would check out Gelligs End Game Boss tank build...its always on the front page of this thread. GLHF

Blood Magic is pretty sexy for Levels x-60 (where x is the level you get to the keystone).
It simply removes mana cost from the game, as you can support pretty much anything with life leech and life regen.

Later on, Auras tend to become very strong, then you can respec out of it.

To use BM lategame, I'd go for some "low life build".
Use Solaris Lorica (Shavronnes if rich) and a lot of Energy Shield, and run a couple of auras on your life pool.