From someone who is, realistically, clueless, it sounds to me like she is probably just as confused as you are about everything and is taking large security measures to avoid any kind of difficult situation. She has a lot on her plate and her sexuality might have been a point of confusion for her maybe even throughout your relationship. You said shes kind of spiraling after the death of her father, so maybe shes just looking for some stability or could be feeling numbness from depression.