I agree with Rusty and with your Dominican friend.
If you say "espero que me hubieras dicho...", it might imply a very strange situation: if there had been a situation when there was a party and I wasn't told, I expect that any time it would happen you would tell me about it.
If you say "esperaba que me hubieras dicho", then you expected in the past that you were told about the party.
Another kind of constructions would have been needed to express you wish now that you had been told before that there was a party:
- Ojalá me hubieras dicho que había una fiesta.
- Me habría gustado que me dijeras...
- Desearía que me hubieras dicho... (this one sounds a little dramatic for me.)
...
...also simply just Rusty's option or...
- ¿Por qué no me dijiste que había una fiesta?