The human mind has quite an amazing memory bank, and we can remember experiences and events that go a long way back.
But we can also forget about some things.
Other words that are connected with forgetfulness are absent-mindedness, carelessness, neglect, negligence, etc.
It could also mean that after a while the memory fades because we don't think about it often or that we choose not to remember.
In the 1st reading, the people of God lamented that the Lord had abandoned them, and that the Lord had forgotten them.
But the truth could be that they had forgotten what the Lord did for them and the precepts that He had laid down for them.
The Lord retorted by asking them does a woman forget her baby at the breast, or fail to cherish the son of her womb.
And even if these forgot, the Lord God will not forget His people.
In the gospel, Jesus said that His aim is not to do His own will but the will of His Father.
May we always remember that our aim in life is to always do God's will, and we will not forget who God is for us.