It should be clear to that if the gatherings or parties you attend are filled with backbiting, slander, showing off and competing in fashionable clothes, you do not have to accept such invitations. Rather it may even be considered haram for anyone to do so, if we are unable to change the reprehensible things (munkar) or if your attending the gatherings will affect your duties towards your deen and family and prevent you from taking care of them.
Sheikh M. S. Al-Munajjid, a prominent Saudi Muslim lecturer and author states: “It was narrated that Abu Hurayrah (may Allah be pleased with him) said: I heard the Messenger of Allah (peace and blessings be upon him) say: “The Muslim has five rights over his fellow Muslim. They are: returning greetings, visiting the sick, attending funerals, accepting invitations, and saying Yarhamuk Allah (may Allah have mercy on you) when he sneezes.” (Reported by Al-Bukhari and Muslim)
The scholars divided the invitations, which a Muslim is commanded to accept into two categories:
1– An invitation to attend a wedding party (walimah). The majority of scholars say that it is obligatory to accept such an invitation, unless there is a legitimate Shar`I excuse. The evidence that it is obligatory to accept this kind of invitation is the Hadith narrated by Abu Hurayrah, that the Prophet (peace and blessings be upon him) said: “The worst kind of food is the food of a wedding feast that is withheld from those who would come, and to which people are invited who may refuse it. Whoever does not accept the invitation has disobeyed Allah and His Messenger.” (Reported by Al-Bukhari and Muslim)
2– An invitation to various kinds of gatherings other than wedding-feasts. The majority of scholars say that accepting these invitations is mustahabb (recommendable), and no one differs from that except some of the Shaf`is and Zahiris, who said it is obligatory.
At the same time scholars have stipulated conditions for accepting an invitation; if these conditions are not met then it is neither obligatory nor mustahabb to accept the invitation, rather it may be haram to attend. These conditions were summed up by the late Sheikh Ibn `Uthaymeen, a prominent Saudi Muslim scholar, (may Allah shower mercy on his soul), who said:
(1- There should be nothing objectionable (munkar) in the place where the party is to be held. If there is something objectionable and it is possible to remove it, then it is obligatory to attend for two reasons: to accept the invitation and to change the objectionable thing. If removing the objectionable thing is not possible, then it is haram to attend.
2- The person who invited him should not be someone whom it is obligatory or Sunnah to avoid or disown, (such as the person who openly commits immoral actions or sin, where forsaking him may be a means of bringing about his repentance).
3- The food offered should be permissible to eat.
4- Accepting the invitation should not lead to ignoring a more important duty; if that is the case then it is haram to accept the invitation.
5- It should not cause any trouble to the person who is invited. For example, if he has to travel or if his family need him, and so on.) (Al-Qawl Al-Mufid, 3/111).
Some scholars added:
6- If the host issued a general invitation, saying that everyone is welcome, then it is not obligatory to accept the invitation.
From the above it should be clear to you that you do not have to accept such invitations, instead it may even be considered haram for you to do so, if you are unable to change the reprehensible things (munkar) or if your attending the gatherings will affect your duties towards your husband and children and prevent you from taking care of them, which as you said, is your primary duty. Moreover, if you attend you will not be safe from their evil and harm, and this frees you from having to accept the invitation, which under normal circumstances you would be obliged to accept.
Women should also note that they have to ask their husband’s permission before attending gatherings etc. to which they have been invited. You should advise these sisters to try to make the best use of their time and their gatherings in ways that will benefit them both in this life and the next. The Messenger of Allah (peace and blessings be upon him) warned us of the consequences of attending gatherings in which Allah is not mentioned. He (peace and blessings be upon him) said: “No people sit in a gathering in which they do not remember Allah or send blessings upon the Prophet, but they will regret it. If He wills He will punish them and if He wills He will forgive them.” (Reported by at-Tirmidhi)
Convey this advice to them, either verbally or in writing. In addition, you could invite them to your house and make the most of this opportunity to have a short lesson about Islam, on any point of interest to the women, including Islamic manners, etiquettes of dealing with others and so on. Along with this, you could have some permissible activities that they would enjoy. Perhaps Allah will make you the means of starting a positive trend in having gatherings that are beneficial.”