What are the idioms that mean inseparable?

To express an inseparable idiom:

Lingering: lingering: depressed; Tender: inseparable. Describe the deep feelings, inseparable.

Difficult to divide: divide: leave; Put it down. Describe a good relationship and don't want to be separated. Also known as "inseparable".

Stick together like glue and paint. Describe the passion, inseparable. Refers to love.

Glue-like paint: Stick together like glue and paint. Describe the passion, inseparable. Refers to love.

For example, glue and paint: just like glue and paint, they are inseparable when stuck together. Describe deep feelings and intimacy.

Glue: To bond like glue and paint. Describe the passion, inseparable. Refers to love.

Like paint like glue: describe love and affinity, like glue like paint.

Stick together like glue and paint. Describe the passion, inseparable. Refers to love.