You could work practically under any moon phase. To banish temptation or your fear of imagined infidelity, perform this spell under a dark or waning moon. To increase commitment or fidelity in your relationship, work this spell under a full or waxing moon. Lost Love Spells. So are you feeling heartbroken over the love lost in your relationship? Has your lover left you for someone else? Feeling desperate to win him back into your life and restart your relationship with more and a better understanding? This love spell will help you achieve your true love. This will create positive energy when I cast the love spells.