My ex left me for another man, but we still have sex. How do I break the cycle?

Dear Julia,

After going on vacation with my girlfriend, she told me she was interested in someone else. Then, I found out she'd been dating him behind my back.

She claims that she still loves me, but also feels she's in love with him. Needless to say, I decided to end our relationship, even though I was devastated and depressed.

She keeps making excuses to spend time with me even though she says she has no intention of leaving the other guy. She's invited me to be with her, and since I still have strong feelings for her, I have succumbed to temptation.

We have sex regularly, and my hope is she'll come back to me and realize she made a huge mistake.

I know she's using me and I feel like a fool for allowing it. I don't enjoy the situation, but feel unable to move on without her.

She was the love of my life and I just don't know how to get over her. Where do I go from here?

- California

Dear California,

I'm sorry you're struggling to find your way after your breakup. Setting boundaries with yourself and your ex could help you heal emotional wounds and break the cycle.

To start, create a support system outside of your ex and reflect on your relationship in a realistic way, Chloe Carmichael, a New York City-based therapist who specializes in helping patients move on from breakups, previously told me.

According to Carmichael, people often cling to past lovers because they haven't created other outlets for their difficult emotions surrounding the split.

To prevent backsliding when your ex reaches out, ask a handful of your most trusted friends and family to be your "breakup buddies," Carmichael told me.

The next time you find yourself about to text your ex or say "yes" to her request for a rendez-vous, call one of your buddies instead.

You don't have to use these calls to discuss your ex if you don't want to — you can talk about anything you want, Carmichael said. The point is to make sure you're getting the support you need from a healthy relationship and boosting your self-esteem.

Consider seeing a therapist as well, who can offer an outside perspective and techniques for boosting your confidence.

Every time you successfully avoid a backslide, your brain is healing from those patterns and creating new, healthy ones.

Set a no contact boundary with your ex

During this healing period, it's also worth setting boundaries with your ex.

This way, you get the physical and mental space you need to build a life independent of her.

For starters, consider deleting your ex from all of your social media, Amy Chan, a relationship advice columnist for more than a decade and author of "Breakup Bootcamp: The Science of Rewiring Your Heart," previously told me.

Chan suggests keeping your ex off of your feed for 60 days and to cut off all contact. You can give them a heads up about your plan.

She suggested saying something like, "Hey, it's not that I don't care about you, but I need this time to heal, take care of myself, and focus on my self-care. For the next 60 days, I'm going to remove you off social media and not have any contact. Please respect my wishes."

If your ex is unwilling to respect this boundary, you can let them know there will be a future consequence for crossing it again, like blocking their number.

Though healing from lost love is a long and complicated process, I know you'll find your way through it. Remember to prioritize your own happiness and goals, and you'll feel more and more like yourself with each passing day.

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