\documentclass[a4paper]{article}

\usepackage[colorlinks]{hyperref}
\usepackage[automake]{glossaries-extra}

\makeglossaries{}

\newglossaryentry{item1see}
{
        name=item1see,
        description={Item 1 see}
}
\newglossaryentry{item1seealso}
{
        name=item1seealso,
        description={Item 1 seealso}
}
\newglossaryentry{item1gls}
{
        name=item1gls,
        description={Item 1 gls}
}
\newglossaryentry{item2}
{
        name=item2,
        description={Item2 2, not like \gls{item1gls} at all.},
        see={item1see},
        seealso={item1seealso}
}
\newglossaryentry{item3see}
{
        name=item3see,
        description={Item 3 see},
        see={item2}
}
\newglossaryentry{item3seealso}
{
        name=item3seealso,
        description={Item 3 seealso},
        seealso={item2}
}

\begin{document}
  I reference \gls{item2}, but none of the others directly in the text.

  \printglossaries

\end{document}
