Death doesn't end a marriage contract
Death doesn't end a marriage contract as the surviving spouses still have duties to fulfill and rights to get even if their relationship has ended this way.
The most evident reason for that is the topic of inheritance:
Allah the Almighty says:
And for you is half of what your wives leave if they have no child. But if they have a child, for you is one fourth of what they leave, after any bequest they [may have] made or debt. And for the wives is one fourth if you leave no child. But if you leave a child, then for them is an eighth of what you leave, after any bequest you [may have] made or debt. ... (4:12)
This verse is a general statement and therefore it applies in any case as long as the 'aqd an-Nikah or the marriage (contract) fulfilled all conditions for a valid marriage in other words even if either of the spouses dies before consuming the marriage as the following report shows:
Abdullah ibn Utbah ibn Mas'ud said: Abdullah ibn Mas'ud was informed of this story of a man. The people continued to visit him for a month or visited him many times (the narrator was not sure).
He said: In this matter I hold the opinion that she should receive the type of dower given to women of her class with no diminution or excess, observe the waiting period ('iddah) and have her share of inheritance. If it is erroneous, that is from me and from Satan. Allah and His Apostle are free from its responsibility. Some people from Ashja' got up; among them were al-Jarrah and AbuSinan.
They said: Ibn Mas'ud, we bear witness that the Messenger of Allah (ﷺ) gave a decision for us regarding Birwa', daughter of Washiq, to the same effect as the decision you have given. Her husband was Hilal ibn Murrah al-Ashja'i. Thereupon Abdullah ibn Mas'ud was very pleased when his decision agreed with the decision of the Messenger of Allah (ﷺ). (Sunan abi Dawod)
The hadith of Birwa bint Waashiq is also mentioned in the sunan books.
In other words what is essential for the verse above is the correctness of the description of the spouses as husband and wife after a valid marriage.
Further the waiting period is a duty on the wife as stated in:
And those who are taken in death among you and leave wives behind - they, [the wives, shall] wait four months and ten [days]. And when they have fulfilled their term, then there is no blame upon you for what they do with themselves in an acceptable manner. And Allah is [fully] Acquainted with what you do. (2:234)
As for the second part of the question it is a tafsir topic I'd prefer having this asked separately. However here the term
was explained as to be referring to your believing wives -which is the majority view based on which your translation has been made- or mates -for example in believe- be it males like sons, brothers, friends or others or females, such as daughters, wives, female relatives etc. it was also explained as the huris.
Imam al-Qurtobi quoted these three explanations in his tafsir (See here):
In the following I'm translating from Arabic language as these translations are mine take them with the necessary care!
( أنتم وأزواجكم ) المسلمات في الدنيا . وقيل : قرناؤكم من المؤمنين . وقيل : زوجاتكم من الحور العين .
(You and your spouses) Muslim wives in this world. And it was said: Your peers from among the believers. And it was said: Your wives from Al-Hoor al-'Ain.