It is not forbidden
Sheikh Mateen Joshua Charbonneau achieved a certificate from Harvard University in Islamic Studies. He undertook Howza classes under esteemed scholars since 2013 and has been teaching at Imam Mahdi Howza since 2017. He has compiled and published several books, has filmed several documentaries on Islamic subjects and has also promoted Islamic propagation in US jails.
If you urinated before the ghusl, then no further ghusl is required in this case.
There is also reward in reading the translation.
"…Said those who prevailed in the matter, "We will surely take [for ourselves] over them a masjid." Quran 18:21
We can understand from this ayah, about the people of the cave, the permissibility of building masajid at burial sights of respected individuals.
Also, refer to Kamil al Ziyarat for many narrations about the significance of visiting Imam Hussain's (as) shrine.
Atheism is denial of Allah as the Creator, while shirk is associating partners with the Creator.
The best thing for you to do in this situation to safeguard yourself is to introduce her to a knowledgeable Muslim sister who can help her.
We should strive to maintain our family relationships and not break them off.
We do know that when the believers were exiled into the valley of Abu Talib (as) that Khadija (sa) was not able to do trade with others due to the sanctions placed upon the Muslims.
This is unfounded as for starters you are not telling Allah to say, rather this is Allah's words addressed to the Holy Prophet (s) and the believers. It is highly recommended to say surah ikhlas in prayer and it is disliked to abandon this surah for a whole day.
A good sermon to read regarding this is the 1st sermon of Nahjul Balagha
You can give charity on their behalf, pray for them and also bring awareness to others about their situation. We must pray for the return of Imam Mahdi (aj) which is the solution to end the oppression in the Earth.
According to a prophetic narration, we must stop oppression by our hand if we are able, if not then we speak against it and if we are not able then the last step is to hate it in our heart.