Conversation so far:
What year did he marry the first time?
1933.
Who did he marry?
Mandl.
Where did they meet?
CANNOTANSWER.
Where were they married?
CANNOTANSWER.
What happened during their marriage?
Lamarr's marriage to Mandl eventually became unbearable.

Question: Why?
Self-contained rewrite: Why Hedy Lamarr?