May her memory always be for a blessing!! Your family's faith in G-d is strong and your blessed mother passed this strength to her children and grandchildren. In my faith, the one year anniversary of someone's passing (Yartzeit) is very important as well. Thought I would share a bit more about it and hope it is meaningful and brings some comfort at this time and always...
The anniversary of the date of passing is very significant in Judaism. Kabbalah teaches that all the spiritual achievements of one's life, including every positive thought, word, or deed, radiate and are revealed in the world and in the Heavens on that day.
On the Yartzeit (Yid. "anniversary"), the soul is at its greatest strength and in its fullest glory. With each ensuing year, this radiance again shines forth in the world and in the Heavens, as the soul is elevated to a higher spiritual level and drawn even closer to G‑d.
While the spiritual radiance from above can influence those below, children of the deceased (as well as students, friends, relatives, even strangers) can similarly benefit those above. On this day, every mitzva performed and every effort to improve one's spiritual life brings great merit to the deceased. This is especially true for one's father and mother.
A Deeper Perspective
A Yartzeit is generally associated with two mixed feelings. On one hand, we learn from our sages that the soul of the departed rises from one spiritual world to a higher one. This is, therefore, a day of rejoicing for the soul, hence a day of corresponding joy for the near and dear ones left behind. On the other hand, the Yartzeit naturally emphasizes the loss sustained by the family, which results in a feeling of sadness. In truth, however, the Yartzeit should not call forth feelings of sadness, but rather a feeling of reflection, self-examination, and repentance.
During this day, one should work to align one's life on this earth to the path followed by the soul above, which is constantly on the ascent. This is to say, just as the soul continuously rises year after year, going from strength to strength, so must those associated with the soul steadily rise in their advancement in Torah knowledge and observance of mitzvot. By doing so, they give the soul of the departed the greatest possible joy.
- This approach underlines the basic view of Judaism that, in reality, there is no "death" in matters of G‑dliness. Rather, the Yartzeit, and even the very day of passing, represents a transition. But this transition is unique for it goes in only one direction — higher and higher, from strength to strength — first in this world, and later in the following world.