Mo . . men . . . tum . . . .

The Oxford English dictionary defines it as 'the force or energy with which a body moves'.
However you describe it, it's all too easy to lose it, when studying Spanish, especially if you're doing it alone, with an Audio, Video or PC/Internet-based program.
There are countless distractions, and excuses not to do it Today.
You take a holiday, then come back and find you can't quite fit it back into your schedule.
You might begin to feel as if you're not making much progress, or you come across a subject which you're struggling with.
Whatever the reason, we all have times where we lose momentum and, if you don't take steps to correct it, you could end up never getting around to picking it up again, and all the work you've done will be wasted.
First, remind yourself why you decided to learn Spanish in the first place. If those reasons are still valid, you still have motivation to carry on.
Remind yourself of how much you're already learned. Dig out some of your old exercises, or redo some of the early tests and exams you completed when you were just beginning. How easy are they now?
Rather than having a break from Spanish, just have a break from the track you're currently following (before it becomes a rut ;¬)
Experiment with some other learning sources, try out some of the free online content I've mentioned in previous posts. Watch Dora the Explorer, or Handy Manny with your kids (or, if you're feeling adventurous, you can watch Dora in Spanish! Just search YouTube)
Speaking of kids, if yours are learning Spanish at school, and aren't yet at that age where any inetraction with Parents is taboo, why not join in when they're doing their homework, or try and engage them in a chat?
The best cure for a stall in your Spanish learning is to find opportunities to speak it.
SecondLife I've mentioned before, is a great place to meet Spanish speakers whether you're typing, or actually using voice.
You can find chat partners at busuu.com,there's a forum at spanishdict.com, and I've just heard about an 'intercambio' site at http://www.verbling.com/, where the idea is to speak 5 minutes in English with a native Spanish speaker, then switch to Spanish for another 5 minutes (thanks to Ben at http://www.notesinspanish.com/, for the link)
Of course the best boost would be a week or two on holiday in Spain (I wish)
If,after all that, you're still wondering whether it's worth pressing on, I can only draw on personal experience. I have always found that the Spanish are delighted to find out that you have taken the time to learn their language. They don't take it for granted like we English do, and will go out of their way to be supportive and patient.
I remember sitting in a beachside cafe in Corralejo, Fuerteventura, and I asked the waiter, in Spanish, if we could possibly have one serving of Tiramisu, with two spoons, as we weren't too hungry. He grinned, from ear to ear and said 'Hombre, por supuesto!' ('course you can, Mate!) and fetched us a portion that would have served three, but charged us for one!
A strange coincidence is that, sitting in the same restaurant were a couple who we had once met through mutual friends, who had been trying to decide whether to approach us but, when they heard me conversing in Spanish decided that they were mistaken, we must be locals, and didn't bother! We didn't find out until we were back in the UK.
Right, that's enough for tonight, I'm off to sign up for an intercambio, at verbling. I'll let you know how it goes. ¡Hasta pronto!