What also keeps bothering me is that it's no surprise that, when I visited Rhonda, the tarot card reading she gave was starting to make sense. The first reading she ever gave me and Dimitri also came true. There was definitely hostility, definitely deception, and I definitely had an enemy or multiple enemies. At this point I was unsure who my enemies and who my friends were. At the time I thought one of my enemies was the queen, but not so much now.
I already knew that the Strigoi was my enemy, they were enemies towards many people, but me in particular because according to Dimitri, I pissed off so many Strigoi in my quest to save him, but with all the protection in place at the court it would appear quite impossible for a Strigoi to take revenge by killing the queen in order to punish me. We would have heard that the wards had been broken and something tells me that a lot more people would have been killed, not just the queen.
What didn't make sense was that the guards apparently didn't notice that there was an intruder until she was found dead. Wouldn't the guards protecting the queen have noticed that a crime was taking place? I am sure that the queen would have made some kind of noise that would have alerted them that someone was there other than the queen.
The murder had to have been someone with the ability to make people think they are not actually there or that someone else is doing the crime.
It could not have been a Strigoi because of the wards in place, so it had to be a moroi, which means there is a strong possibility that they were no longer moroi; however, I have witnessed cases where someone had the ability to enter one's mind and manipulate them into killing themselves. Whoever killed the queen would definitely have to have been a moroi with strong abilities.
I have also witnessed those with the ability to mask spirit. Although both Lissa and Adrian can now sense other spirit users, it might still be possible that one still lived among the courts or decided to visit. It is possible that that person got into the queens mind and got her to kill herself.
Whoever the murderer was, it wasn't me.