Like the song proclaims, "Breaking-up is hard to do." Futhermore, ending a relationship in which you were truly invested and severing all ties can be the most painful experience of all.

So how can you tell when it's time to stick it out and work on the relationship, or admit things aren't working and move on? Here, 10 signs to look for that will tell you it's time to split. You'll know a breakup is imminent and necessary when:

1. The relationship feels toxic, with physical, verbal or emotional abuse by one partner. Abuse is a huge red flag and calls for a quick and final breakup, says Stacy Kaiser, MA, MFT, and author of How to Be a Grownup.

2. You find yourself complaining to your friends on a regular basis about your partner. "Everyone has their moments," says Kaiser. "But if you are complaining about the person all the time, it's not good."

3. You stop making time for each other and have no interest in fixing problems in the relationship. This may signal that it's time to move on, Kaiser says.

4. The other person acts very preoccupied, says Mary Jo Rapini, LPC. "This can often occur with clinginess," she says. "Or you may find the person becoming more possessive."

5. Your partner becomes more irritable than he or she usually is. "You may also notice that there is more conflict and more criticism," Rapini says.

6. Your partner withdraws sex. "This is a really bad sign, especially in a man," Rapini says. "Men don't usually use that tactic, and if they do it means that they are looking for someone else."

7. Your partner starts talking about his or her ex a lot more than usual. "What is happening here is that the love and the enamored feelings for you are starting to wear off and the person is beginning to see the flaws," Rapini says. "The person is almost starting to see you as an ex."

8. Your partner stops planning future events with you. "If you notice that your girlfriend or boyfriend is no longer inviting you to things, it may be a message," says Whitney Casey, author of The Man Plan and a relationship expert for Match.com. "And if they start taking a lot of calls outside of the house, they may be out dating again and are trying to get something nailed down with the new person."

9. Your partner is suddenly working a lot of overtime and doesn't want to spend time with you. "And if he or she becomes very protective of his gadgets such as a computer and cell phone, this is a sign that a breakup may be imminent," says Belisa Vranich, Psy. D.

10. The person becomes more possessive and more controlling, Rapini says. "This means he or she could be trying to move too fast into the next stage," she says. "If someone moves too quickly and becomes almost overly charming, that's a sign that it is time to get out of the relationship."