“You can use mantras, breath, or the quiet glow of a candle. Your technique is not important as long as you know this one simple thing: it is natural for thoughts to arise during meditation. You will say your mantra, then you will forget it as a wave of thoughts flow through. Then you say your mantra again. Simple as that. So, too, if you are meditating on your breath. You will feel your breathing, then you won’t… because a herd of thoughts stampedes across your mind. This is perfectly natural. Perhaps that herd has been penned up for a long time.

Thoughts long hidden within you arise when you meditate. Allow these thoughts to arise so they can dissolve in due time.
Please ignore those well-meaning, earnest teachers who tell you to “stop” thoughts or “give up” attachments. To try to stop your thoughts is like swatting at buffaloes. Amusing for the buffalo, a waste of effort for the swatter. Watch the buffalo stampede, then return yo your mantra, return to your breath. No stampede lasts forever.”
~ Ramana Maharishi