W. Austin Gardner
Condition of man in the last days

II Timothy 3:1 This know also, that in the last days perilous times shall come. 2 For men shall be lovers of their own selves, covetous, boasters, proud, blasphemers, disobedient to parents, unthankful, unholy, 3 Without natural affection, trucebreakers, false accusers, incontinent, fierce, despisers of those that are good, 4 Traitors, heady, highminded, lovers of pleasures more than lovers of God; 5 Having a form of godliness, but denying the power thereof: from such turn away.
Unthankful/ungrateful
People take everything for granted. We feel it is owed to us. Notice how God ranked this attitude in Romans 1:21
Because that, when they knew God, they glorified him not as God, neither were thankful; but became vain in their imaginations, and their foolish heart was darkened.
Right after not glorifying God is not being thankful or grateful. The lack of gratitude is a severe problem rooted in a selfish, self-centered heart.
Many never see the privileges and blessings that they have been given. They do not notice what others do for them. They are takers and forget all thanksgiving they owe to God or their fellow man.
The unthankful refuse to recognize the debt they owe to God and others. They refuse to acknowledge that God is doing something in their lives. They see it all as what they do or deserve.
They begin to think that they are better than others. They deserve the good. They believe others should be thankful, but they are the giver.
Unholy
The unholy resist any idea that they should measure themselves by God's standards. These people are mastered by their lusts, passions. They seek to please themselves. They feel little shame or embarrassment. They seek pleasure in things that God hates.
This word would refer to being in opposition to God and holy things. It means feeling no need to honor God or man. This person is separated from God and consecrated to sin.
It is the idea of ignoring the decencies of life. They offend God and even the unwritten norms of life.