Glitch sims 3, won't finish kissing or propose going steady

Can you give some more details?

What do you mean by not finish kissing?

You have to do a lot of romantic actions in a row until the other sim thinks that your sim is being extremely irresistible, only then will the options for going steady or proposing marriage will appear.

see if this thread will help you http://answers.ea.com/t5/The-Sims-3/Glitch-sims-3-won-t-finish-kissing-or-propose-going-steady/m-p/1136586/highlight/true#M51884