Stop yelling

Her dislike for the Yi family ran deep with roots spanning a great distance. She worked with the Marshal but she also blamed him for letting her husband die and that blame extended to the Marshal's offspring.

When her husband was attacked and requested for backup the Marshal was nowhere to be seen and when she officially asked for them to find the person who committed his Royal Highness' murder all she got was sympathetic looks and threats.

She was told to let it go or risk losing the Bloodgarde so yes she had great hatred for the Marshal and all his Generals. Such blatant betrayal made her want to instinctively protect her son.

The Yi family used people and once they had no use for them they abandoned them. They used her husband to consolidate their power and maintain their exclusive rights to the military but when her husband's ashes were scattered on that dead planet they didn't avenge him. They only performed a shoddy funeral service and that was it.