The situation is, I delete a contact from my gTalk contact list. I’m not sure if my contact details have also been deleted from his or her account.
Technically looking at it, you have no control over your contacts account, so you will not be able to delete your contact details from his account. But you can control this situation by blocking the person from your account, till the time you want them to be blocked.
Please refer to this post: How to block a contact on GTalk
By blocking a person this way, you’ll not be online for them anymore. But the flip side to this is that, you too will never be able to see if the person is online or not.