How can I get through the grave yard?

Very carefully. The undead/unholy/whathaveyou creatures can be rather irritating. Especially when invisible.
A good solution is first going back to other places and leveling up more, but that's a last resort (of course, unless you've been slacking and you're a much lower level than you should be)
To get the icky poison barriers off of vital items, use Clear (the white-ish blue spell) beneath it. To make invisible monsters (the ones that are just an outline and a red dot) appear, any holy spell is sufficient (I.e, cure, clear, raise, your last three spells there)
I am always sure to have one of each race with me at all times. I'm usually a Selkie or a Clavet (however the heck you spell this stuff). It's nice to have a Lility with you instructed not to use magic. Lilties are very resilient, even though they don't do much damage, and if the rest of your party dies, you have a Lility to revive them with, as they'll have a full mana bar.
Be sure to always have a... Oh my the name of the race has slipped my mind. The ones with the metal helmets and bad@ss magic skills. Be sure to always have one with you, and be sure to equip it with a staff. A good staff. And change it's AI setting to Use Magic Like Crazy (or whatev). It will heal you whenever you are in a jam.
Because the AI in this game can't fend for itself work crap, you will have to juggle characters a lot, and be prepare to wear out your "R" button calling them back to you, especially when in that one room where you have to move the coffins around like crazy (what am I talking about that's like every room).
The final boss is the Ghost Princess. She's a b-I-t-c-h. Especially if you don't have a Selkie to jump on her and stomp on her weak point (that's what she said). You have to periodically cast a holy spell on her to take her out of invisibility, and she likes to charge across the battlefield trailing huge things of fire or ice behind her (sort of like in the first game when you threw a magicite orb) which your AI companions will be too stupid to dodge. As I said, spam the R button. A bow may be worth utilizing, but only when you can't get close to her (Actually, I recommend using a bow - a good one - whenever you fight Larcaiceus (however the f*ck you spell it), especially the final battle, but I won't go into detail because spoilers.
Hope this helped, you or anyone else looking for answers.