First you’re smitten by a social network or Web service and can’t stop spending time on it. Then it starts asking how you’re feeling, what you like, where you are, with whom, and why you don’t share as much anymore.

Pretty soon, you’re ready to call it quits.

But trying to end your relationship with some prominent online services can be like breaking up with an overly attached romantic partner — they make it pretty hard to say goodbye.

And with good reason — more users are beneficial to a company’s bottom line, which often depends on generating revenue by selling you targeted advertisements. Possibly no social network understands this better than Facebook, whose chief executive, Mark Zuckerberg, proudly announced last October that his site had surpassed one billion active users.

“Their business model is about getting users to create content,” said Jeremiah Owyang, an industry analyst with the Altimeter Group. “It’s users who are creating content, liking things, and, ultimately, a brand sees this and comes to deploy advertising dollars. The product is us.”

Still, not every site takes the “Never Gonna Give You Up” approach. Alexis Ohanian, the co-founder of the social news site Reddit, said that if users wanted to delete an account, “they should be able to do that as easily as they signed up.”

“It puts the onus on us to keep delivering a great product, and not retaining users simply because they can’t find the exit,” he said.

And remember, even if you say goodbye, like Rick and Ilsa in “Casablanca,” you’ll always have Paris.

FACEBOOK Given Facebook’s history of privacy controversies — and its general tendency to occupy vast amounts of time — some people may eventually feel the need to leave, or at least take a break from the service.

To quit entirely, log on to your account and go to https://www.facebook.com/help/delete_account. After hitting the Delete My Account box, you’ll be asked to enter your password.

If you want to download a copy of your photos, posts and messages before leaving the service, you can do that from the account settings page, which can be quickly reached by clicking on that little round gear icon at the top right of the Facebook home page.

Unlike many sites, Facebook gives you 14 days to change your mind before your account is permanently deleted. The company knows it has hooked hundreds of millions of users, many of whom won’t be able to stay away and will come crawling back.

The site will also let you take a temporary break from the relationship by letting you deactivate your account. Unlike deleting, deactivating it will merely disable your profile, although some features, including sent messages, may remain visible to others. You can return at any time, with your information intact.

But Facebook makes it harder to put the relationship on hiatus than to leave permanently. Before you can deactivate your account, Facebook asks you to provide a reason for quitting. Choices range from “I spend too much time using Facebook” to “I don’t understand how to use Facebook.” For nearly all selections, the company pleads with you to stay. Don’t find Facebook useful? It responds by advising you to connect with more friends.

According to a Facebook spokeswoman, this is less about being clingy, and more about being consumer-driven by giving users “the power to decide what action is right for them.”

After selecting your reason for leaving, hit Confirm. You’ll have to re-enter your password, then hit the Deactivate Now box.

Not surprisingly, Facebook ends things by saying, “We hope you come back soon.” Which, let’s face it, you probably will.

GOOGLE PLUS Google tries to entangle you in multiple, distinct services like Google Plus, Gmail and YouTube — all connected. And it can track your activity across all of them and show you ads.

But the company doesn’t hassle you before letting you leave. To delete your Google Plus social network profile, log in and hit the gear icon, which is directly to the right of the View Profile As tab. From there, choose Settings and scroll all the way down the page, where you should see a Disable Google+ tab that gives you the option to delete just Google Plus content or your entire Google profile.

It’s important to note what does and does not get deleted if you drop Google Plus alone. Circles, Plus 1’s, posts, comments and third-party app activity will all be gone. Photos won’t be deleted; you have to remove them through Picasa Web Albums if you want them gone. Your chat buddies and communities are also kept intact.

Alternatively, you can hide elements of your profile. Go to the About tab on your profile, and hit the blue Edit link to change what others can see.

AMAZON Amazon has created one of the most difficult opt-out procedures of the major sites. Under the Your Account section are countless blue links, continuing as you scroll down. There is no sign of a “close account” option anywhere.

Turns out, there isn’t one.

To close shop, you have to go to www.amazon.com/gp/help/contact-us/account-assistance.html. Then you have to select Something Else in Section 1, and Account Settings then Close My Account from the drop-down choices in Section 2. In Section 3, you’ll see e-mail, phone and chat contact options. Before going through all that rigmarole, it’s best to first remove your credit card information to guard your privacy. Go to the Your Account Page, click Manage Payment Options located under Payment Methods, and delete the information on file.

LINKEDIN Though LinkedIn makes it easy to close your account, the company reserves the right to use your data for marketing and other purposes — closed account or not.

To terminate, log in to the home page, select the Settings tab located in the drop-down menu under your name in the upper right of the screen. Next hit Account, followed by the Close Your Account link.

For privacy reasons, it’s a good idea to remove all third-party applications first. To do that, click on Groups, Companies & Applications located above the Account box, hit the View Your Applications link, check the apps you want removed and hit Remove.

MYSPACE Like many people, you may have had a youthful dalliance with this once-popular social network. But even if you moved on long ago, Myspace didn’t. It never forgot you.

To cut ties once and for all, it’s easiest if you remember your password and have access to the e-mail address that you used when signing up. If so, head over to the My Stuff tab, choose Account Settings from the dropdown menu, and select Cancel Account under Account Settings & Privacy. You will receive an e-mail from Myspace asking you to confirm your request.

If you can’t log in to that old e-mail account, don’t worry: Myspace will let you close the account after you prove your identity by completing a declaration form athttp://myspace.desk.com/customer/widget/emails/new. When filling it out, move on if you can’t remember a detail because the company may well be able to process the form anyway. But be patient — the company says it is dealing with a backlog of requests.

TWITTER Twitter likes to communicate. A lot. By default, it will e-mail you constantly.

To cut those back, hit the gear button on the home page, scroll down to Settings, then hit the Email Notifications tab and choose which of the 16 or more types of e-mail from Twitter that you no longer want to receive.

If you want to leave the social network altogether, go back to the Settings page, scroll all the way down to the bottom, and click on the tiny Deactivate My Account link on the bottom.

Twitter gets a tad emotional at this juncture: “Is this goodbye? Are you sure you don’t want to reconsider? Was it something we said?”

Assuming that you really want to quit, hit the blue Deactivate box and enter your password.

If you want to hang onto the memories — like those tweets from the top of the Eiffel Tower — before deleting your account, you can Request Your Archive from the same Settings page, just above the link to deactivate.

OTHER SITES The Web sites Delete Your Account (www.deleteyouraccount.com) and AccountKiller (www.accountkiller.com) have compiled extensive deletion information for many sites.