All right, here's what we know so far:
We know that the Queen, Raph's mom, is sick enough that she died in the previous go-around.
We know that the Portanians are attempting a hostile takeover, which requires Ork to be on the throne so they can bully him into being a pawn.
We also know that the Portanian plan requires he have both a useless queen consort (Pia) and a useless court (i.e., only those sycophants who kidnapped Coco that one time).
Saravia does not want her original country's plan to succeed, because she hates them and their sexist country.
Luna wants to marry Ork for love.
The Queen wants Luna to marry Raph for factional consolidation.
Luna's shadow isn't stopping these incidents, and Luna herself seems unwilling to accept help.
Pia is almost certainly Gob's pawn, and is trying to paint Coco in a horrible light.
So here's my thought. Luna is too scared of the Queen to overtly oppose her, since she has to rely on her father for protection — and her father is probably in Her Majesty's pocket. The Queen thinks Saravia is supporting the Portanian plan because she's from Portania, unaware that Saravia despises her homeland and would rather see them burn than succeed. Thus, she's leaning on her shadow that if Luna isn't going to withdraw her name from Orkhart's consideration, she's going to make her by making her life a living hell.
Pia is plotting all sorts of things, and Luna's Shadow is using some kind of Shadow Magic (as we know Shadow has access to some kind of magical powers, so we can assume that the one assigned to Luna probably has similar powers, if not greater ones from her being the one chosen by the Queen herself) to disguise what Pia's doing. The Queen doesn't recognize Pia as part of Gob's plot, because Pia is a born citizen of Cheriotte, and should therefore want to support her own country.
Gob knows that the Queen wants Luna to marry the Prince, and figures if he can get Luna killed, and take Coco for himself, he can get the Portanian plan to go off without a hitch.
In essence, Luna's being targeted by three different people with three different goals who all see her love of Ork as an impediment to their success (she's too close to the wrong prince for the Queen, she's too close to Ork for Pia, and she's too competent for Gob).
EDIT: Forgot Tear was Phiss's sister, not Luna. Edited to remove that detail.