Stalkers are pretty easy to handle. Just ignore them at first. If that doesn't work, then get your hulk of a bouncer friend or a pretty, female colleague, depending on the situation, to warn them. As a last resort, get a restraining order and keep your wits about you.
What about your ex (currently known as barnacle, limpet, or ball and chain)? It was clear enough to you and just about everyone else that you two had to end it. Not only were things not going anywhere, but also you were positively wilting under the strain. Yet, the ex seems to have missed all of that and continues to be hung up on you. While he/she got the message fast enough about not humming, "we can work it out" and gazing meaningfully at you, the phone calls have continued, wanting to involve you in every small detail of everyday life.
Being on friendly terms with an ex and discussing certain situations with them is a wonderful thing. Wanting them to be supportive of your every move and hold your hand through your every crisis, or reminding them at every possible opportunity of your undying love for them is not. If you are stuck with one of these thoughtless exes who just cannot let go, you absolutely have to take action to get your life back and move forward.
There is no point sugarcoating anything just to make the other person feel better. Offer only what you can, and no more. This means avoiding those sweeping "I'll always be there for you" and "You're a part of my life" type of statements. Tell them in words that are neither unduly honeyed nor harsh, that what is over is over and that you cannot have the same level of emotional intimacy with them any more. Say the words as often as you need to.
Don't prolong the agony
It may seem paradoxical, but do try to make this easy for them. Not the break-up itself, because that is what it is, no more and no less. When it comes to telling them that it is time they let go, make it one swift blow rather than a series of hints and insinuations: those small wounds that hack away at their peace of mind and self-esteem. This is the least that you owe yourself and them. Hints are often misunderstood, and insinuations throw the other person into a lather of speculation. Do it quickly, and you can both move on with your lives.
But also take it slow
Once you have made the break, and after you have handled any signs of "the clingy ex syndrome," take it very easy. It is, of course, possible that when the intensity of emotion brought on by the loss of love diminishes, you could be the best of friends. However, you have months and years to make that happen. If your non-couple connection is strong enough, it will endure the wait. There is no hurry to get back into any kind of relationship with each other, not even as "just friends," or confidantes, or tennis partners. Allow the time to process the break-up
and when you are both ready, one will make the move and the other will respond.
Set them up
All kidding aside, it really could work. At this point, you, more than anyone else knows what is going on in the ex's head. Set them up with distractions, like a common friend or that new person at work. You can even go on double dates
with them and be very nice to your date, so that the message is unmistakable. In many cases, the wound to the ego will ensure that the ex will be equally nice to whomever they are out with, and who knows, there might even be a real connection for them. Any help you give them should be of this kind, pushing them to move on and embrace change.
A strong hand
If all else fails, from your own carefully worded dismissals to the reasoning of mutual friends or family, then you have to be firm. Tell them to just buzz off, not bother you, and go away. It may feel cruel and unnecessary, but in the long run you get your time and mental space back and they know, clearly, that they cannot thrive at your expense.
As strange as it seems, if you look at continually clingy ex situations objectively, there is often a great deal of temptation floating around. If you are the one that got away, then you must resist the temptation to keep yourself open to flattery, confessions of desperate love, etc. Who doesn't like ego boosts? Okay, so your ex makes you feel indispensable or fascinating. Is that reason to string them along? Be careful that you don't complain about an ex's inability to let go while tacitly, on the other hand, giving them continual hope.