Should she go with her mother for ‘Umrah without a mahram or stay at home on her own?
Question

                Is it permissible for a 26 year old woman to go and do ‘umrah with her mother and trustworthy companions, as she does not have a mahram such as a brother, father or husband? Please note that she wants to do ‘umrah even if it is not obligatory for her because she does not have a mahram. If her mother travels for ‘umrah she will be forced to stay alone.
Praise be to Allah.A woman who cannot find a 
    mahram to travel with her is not obliged to do Hajj or ‘Umrah; she is 
    excused for not doing that, and it is haraam for her to travel for Hajj or 
    for any other reason without a mahram. She has to be patient until Allaah 
    makes available a mahram with whom she may travel. 
There are many ways of 
    doing good. If a Muslim cannot do some acts of worship, then he should 
    strive hard in those acts of worship that he is able to do, until Allaah 
    makes it easy for him to do the acts of worship that he is unable to do. 
By the grace of Allaah 
    towards His believing slaves, if a person resolves to do an act of worship 
    but he is not able to do it for some reason, He will still reward the person 
    for it. al-Bukhaari (4423) narrated from Anas ibn Maalik (may Allaah be 
    pleased with him) that the Messenger of Allaah  (peace and blessings of 
    Allaah be upon him) came back from the campaign to Tabook and when he drew 
    close to Madeenah he said: “In Madeenah there are people who, whenever you 
    travelled any distance or crossed any valley, were with you.” They said: O 
    Messenger of Allaah, even though they are in Madeenah. He said: “Even though 
    they are in Madeenah, because they were kept there by excuses.” 
It says in Fataawa 
    al-Lajnah al-Daa’imah (11/90): 

    A woman who does not have a mahram does not have to do Hajj, because in her 
    case a mahram is part of being able to do Hajj, and being able to do it is 
    one of the conditions of Hajj being obligatory. Allaah says (interpretation 
    of the meaning): 

    “And Hajj (pilgrimage to Makkah) to the House (Ka‘bah) is a 
    duty that mankind owes to Allaah, those who can afford the expenses (for 
    one’s conveyance, provision and residence)”

    [Aal ‘Imraan 3:97]

    It is not permissible for her to travel for Hajj or for any other purpose 
    unless she is accompanied by her husband or a mahram, because of the report 
    narrated by al-Bukhaari and Muslim from Ibn ‘Abbaas (may Allaah be pleased 
    with him), that he heard the Prophet (peace and blessings of Allaah be upon 
    him) say: “No man should be alone with a woman unless her mahram is present, 
    and no woman should travel unless she has a mahram with her.”  A man stood 
    up and said: “O Messenger of Allaah, my wife has gone out for Hajj, and I 
    have enlisted for such and such a campaign.” He said: “Go and do Hajj with 
    your wife.” This was also the view of al-Hasan, al-Nakha’i, Ahmad, Ishaaq, 
    Ibn al-Mundhir and ashaab al-ra’i, and it is the correct view, 
    because of the verse quoted, as well as the general meaning of the ahaadeeth 
    which forbid a woman to travel without her husband or a mahram. Maalik, 
    al-Shaafa’i and al-Awzaa’i held a different opinion and each of them 
    stipulated a condition (allowing her to do that), but with no evidence. Ibn 
    al-Mundhir said: they did not follow the apparent meaning of the hadeeth, 
    and each of them stipulated a condition (allowing her to do that), but with 
    no evidence. 
.End quote. 
Just as it is not 
    permissible for a woman to travel without a mahram, it is not permissible 
    for her mother either. She should fear Allaah and stay with her daughter. If 
    she insists on going and that results in the daughter staying alone, then if 
    she is staying in a safe place there is no problem, but if she is afraid of 
    staying alone, then this may be an excuse for her to go with her mother as a 
    case of necessity, and the sin will be on her mother. 
And Allaah knows best.