“My friend competes with me about everything”

What could be going on

Social comparison: Fits if they constantly measure themselves against you; check if it eases when you're struggling.

Inferiority complex (Adler): Could be a felt minus underneath; check whether the competing hides insecurity.

Status motive: Fits if rank and being seen as ahead matters to them in many relationships, not just yours.

Envy: Check whether your strengths are exactly what they compete over.

Mimetic desire (Girard): Could be copying: wanting what you want because you want it.

Also said as

• she has to have a better holiday, a bigger house, a better job
• my friend turns everything into a competition
• why does my mate always try to outdo me
• competitive friend who can't let me win anything
• friend always needs to win
• my friend is in constant rivalry with me