“Staying in the present’ is popular pop-psychology prescription. The evidence suggests a different and more sophisticated attitude to time:

... Zimbardo believes research reveals an optimal balance of perspectives for a happy life; commenting, our focus on reliving positive aspects of our past should be high, followed by time spent believing in a positive future, and finally spending a moderate (but not excessive) amount of time in enjoyment of the present.

-Wikipedia on Zimbardo

So instead of living in the present, try living in the positive aspects of the past, and to a lesser extent believing in the positive aspects of the future, and finally only enjoy the present, like pop-medical advice for other minor vices, ‘in moderation‘.