How would you translate this?Dat valt me van je tegen.

Question

Answer

You disappointed me.

Notice that is meant ironically.
If you really are disappointed you would say it differently.

e.g.
* Ik loop de marathon in 2.30.

- Dat valt mij van je tegen --> That disappoints me. (ironically)
- Je tijd valt tegen --> Your time is disappointing (seriously)
- Je stelt mij teleur --> You disappoint me.

Answer

Dat valt me van je tegen. -  This dissapoints me of you.