I agree with JO3Esq.  She is in absolutely no position to be in a committed relationship when she is technically legally committed already to someone else.  "Separation" is an informal construct -- she can say she's separated one day and then the next, she can "unseparate" herself; there's no documentation that is usually necessary to declare a state of separation.  If she is also wrangling over assets from her marriage to finalize her divorce, it sounds like she is still very much involved in her ex-husband's life and may be for some time.  (Another thing to consider -- once you marry someone, even if you divorce, you have life-long obligations to one another in the form of tax and legal communications that will keep you both linked for all time, basically.  This is not like a boyfriend she can dump -- this guy is always going to be in the picture, even if it is just a tiny part of that.)

Definitely take some time here.  Speak with her about your desire to be with her, and be sure that your relationship with her has been progressing appropriately; but recognize that she is not ready right now from a logistical and legal standpoint, and proposing to her is likely only going to make her feel pressured to give you an answer that she isn't ready to give or an answer she cannot really commit to.