Can a woman suffering from rheumatism, who is unable to bend and finds no one to assist her, omit washing her feet during ablution (wudu’)?

Washing the feet is an obligatory act in ablution, but Islamic law is built upon ease. If you are unable to wash them and there is no one to assist you, then you must wash as much of your limbs as you can, then perform tayammum (definition) (dry ablution) for the limb you were unable to wash, based on the Almighty's saying: "So fear Allah as much as you are able," and the Prophet's saying, peace be upon him: "When I command you to do something, do as much of it as you can." If you are able to get water to your feet by any means, then your ablution is valid.