Feel Like a Third Wheel

What do we say when you feel like an extra person - ignored and not wanted or needed?

 

" feel like a third wheel " 

 

Example 1

 

Junko and Aya are best friends. When I'm with them, I feel like a third wheel . 

 

Example 2

 

I went to my husband's company party. He talked with everyone except me. I felt like a third wheel .