Vampire Academy question

both of them are at fault... i feel bad for Adrian hopefully he will meet someone better in the bloodlines series

Both, because Rose in my opinion played with Adrian.
Adrian for knowing she love Dimitri and she wasnt going to let go of Demitris love, at the end of the series I felt sorry for Adrian.

Adrian did sort of ignore the warning signs but only one of them actually cheated and that was Rose.

I think Rose was at fault. She cheated on Adrian, broke his heart and when he was upset about it she acted like it was all his fault. She never really loved him, but she said she did. He trusted her and she lied and cheated. Though I love her, I will always resent her for that. Adrian's my favourite character.

Adrian may have ignored the signs due to his love for Rose, but she's the one that cheated on him. Adrian didn't make Rose sleep with Dimitri, she made that choice all by herself.

Rose is definitely at fault because ROSE is the one that cheated on him. No matter what Adrian believed ROSE told him she loved him in Spirt Bound. She could of waited to have sex with Dimitri after she told Adria it was over.

i think its a little of both. Adrian knew just how much Rose loved Dimitri and he still wanted to the chance to persue it. Rose knew she would never love anyone like Dimitri and she still tried to make things work with Adrian knowing how fresh Dimitri was to her heart.She knew if she was giving the chance she would take him back in a heartbeat. but bc she thought there was no hope she tried to learn to love Adrian and she really did have feelings for him just not deep like she did dimitri. That was a risky relationship from the beggining. Also, when rose was fixing to the leave the school to find dimitri and "do him a favor" she asked for help from adrian and adrian implied in return when she came back she give him a chance...

well both had faults, Adrian for ignoring the obvious sighs that it wasnt over between them and rose for cheating. Adrian did indeed take advantage of her while she was greving but rose could have talked with him and made everything clear. i think its both of their faults.

Maybe a little of both, but sure Adrian ignored the warning signs but that doesn't excuse Rose cheating on him. He didn't deserve it, Rose should have wait until speaking with Adrian before sleeping with Dimitri. She knew how strong her love for Dimitri was, Adrian knew it too but he was so in love with her that he chose it ignore it which many would when you're in love. So yeah Rose is at fault in my opinion.

In the end, I think it was a little of both
Adrian: he knew that he didn't have a chance & that Rose loved Dimitri more than him. Also, he did take advantage of her grief/favors, in which Rose was too stressed to say "no" to. Plus, Rose was right at the end of Last Sacrifice when she realized that he depended on her: love was about growing stronger with one another's love, not borrowing your strength from the other person. Adrian needs to grow out of his teenage boy stage and realize what love is truly about

Rose: Yeah, she knew that she still loved Dimitri, she thought that there was a chance she might not come back to give Adrian the chance he asked for, and later on she realizes with the help of Adrian's mom that she and Adrian's lives could never coincide in the future. But she like Adrian and gave him the chance he deserved. That's honorable. But she did make the choice to cheat on Adrian with Dimitri and broke her promise to Adrian.

(also a little of Dimitri's fault: so what if it gets hot n' heavy- Rose is beautiful and all, but you're trained as a guardian to have self control, which you should have used knowing that Rose was with Adrian. You could have just waited until she broke up with him!)

In every human 2-people relationship both of them are at fault.
Adrian, well, like many other people have already said, ignored the signs and, in my opinion, he actually knew that Rose wasn't all that hot for him (not as much as with Dimitri, anyway) from the beginning. He actually had to make a deal with her for Rose to decide to give him a chance. And, well, that was it. A chance to see if that would work out. She never said she loved him more than Dimitri, or anything. And, if he wanted her that much, she dicided to try with him to get over her former tutor.
But, obviously, she didn't make it. And, the fact that she slept with Dimitri while in a relationship with Adrian is wrong, but it's not only her fault. She had already decided to break it off with Adrian. The Moroi was so heart-broken mainly because he found out the way he did. I think he would have expected that the love between Rose and Dimitri would fire up again if they were all alone together.
And, anyway, generally when someone cheats it's not only their fault. It's the other person's fault, too. For different reasons every time.
My opinion. And psychologists'.

both...rose because she knew that she still loved dimitri and she went on with her realtionship with andrian and andrian because he understood that rose felt something about dimitri and he ignored it because he said that he loved her...i think is more rose's fault though because she actually cheated on him while he tried to do some many things for her...like stop smoking and drinking..both of them didn't actually appreciate what they had...

Both of them did something wrong, but I do feel sorry for Adrian.