some affections are held in the highest reguard, only when occuring on an idealic level.
if you are approaching this relationship earnestly and not using it to compensate for a lacking necessity in your primary relationship, ie. your husband, then you will find that patience comes easlily.
none the less , you may want to check your want/needs with the understanding that, though, you may provide something for her, it is clear that her husband/family do also. I suspect that she finds more solace in the idea of sharing your famililia then the reality of it.
if i seem gruff please forgive me, i respect polyamorous culture highly and do not want you to feel like im being critical on accout of narrow ethics,...
i notice you mention her son for instance, you didnt seem to reflect on his responce/reaction to your rather bold proposal, nor do you mention the age/gender of the other implyed "kidS" what is the age/gender of her other child ? . Strikes me that you should, if begining a relationship with a lover, aim to empathise with their needs and some needs of their loved ones, you said her critisism of her husband was that he was "self centered" i would take this to heart, and be wary of prioritizing your wants over the "needs" of her children.
imho if you really want to accelerate this process. Find complete fufilment within yourself and you relationship with your husband, you will certenly awake in her awareness of your bliss.
seems to me that you two likely represent a freedom for her which feels oppressed around her husband/childeren, the very conundrum of the mundanity of life. If you were to become her daily bread , then, i suspect, no more could you provide her with trancendance from the ordinary... hark... hear this well, perhaps the greatest struggle we all face is imbuing meaning within our lives.
perhaps your " concern " should be... are you happy? are yours happy?
try it on, see if fits a little better then "are you comfortable with homosexual pda's " (public displays of affection.)
she might just love/need it