There's a guy you totally fancy and whom you've been seeing for sometime. Yet there's something about him you can't put your finger on: He's kinda too busy with work, a tad too passive about your relationship, and not acting as besotted as he should be.

Or maybe he really isn't. It's a bitter pill to swallow, but better to know if he's wasting your time sooner rather than later. Here are five red flags that could confirm your doubts.

1. He's not trying to see you

Either he's the busiest guy on the planet or his sorry-I-got-to-work-on-weekends excuse is just that -- an excuse. How do you know for sure? Does he find time for his mates yet somehow not have time to meet up with you or talk on the phone? If the answer is yes, something is amiss. When it's always you who's doing the running, it's a clear indication that he's not all that committed to the relationship. "If a guy is into you, he will find time to make a call and catch up," says Lexi Proud, who is a dating expert for Arrange Me a Date.

2. You've not met his friends

It's not a good sign if he hasn't introduced you to his friends and family, especially after you have dated for some time. Just how long is too long to wait? Proud suggests asking questions if you've not met any of his friends by the three-month mark and if you've not met his family by six months. "If a guy is into you, generally they want you to meet their friends. After all, they should be proud to have you on their arm!"

3. He only sees you for sex

This is so painfully obvious that it's going to sound blunt. If this guy is only meeting up with you for a hook-up, he's only into your body, not you as a person. Get out, pronto.

4. He often lets you down

Does he frequently cancel plans you've made together because "something else" has cropped up? Be wary, especially if there's no reason for it, and if it's happening on a persistent basis -- it's a sure sign your relationship just isn't up there on his list of priorities.

5. He leaves you in doubt

Here's the simple universal truth about men: If a guy wants you, you'll know it. He won't leave you wondering about his behavior -- he'll call you, he'll ask you out, he'll want to be with you whenever he can. If all you get are lukewarm reactions from the guy, he's just not that into you. Period.