There is no permanent relationship

Is there any psychological security certainty or security such as the mind is always seeking? Obviously when you observe any relationship very closely, there is no certainty. In the case of husband and wife or boy and girl who want to establish a firm relationship, what happens? When the wife or the husband looks at anyone else, there is fear, jealousy, anxiety, anger and hatred; there is no permanent relationship. Yet the mind all the time wants the feeling of belonging.

I only recently realized that when I die, I won't see my children ever again.  Now I live in fear that I'll meet with sudden death and not even get the chance to say good bye and I love you.   Also, when my greatgrandson was born I realized how little of 'me' was contained in his genes!  When my kids were born, I felt like they were "mine".  But at this point, I know my ggson's mother, father, all sets of grandparents, most of his greatgrandparents and a greatgreatgrandmother.  So relationships are temporary at best.