Breaking up has made me a mean person

Broke up with my bf of 6 years and I’ve really been struggling with coping. My best friend got into a relationship right as I finished mine so I felt betrayed. Was passive aggressive with my tone and making jabs at her unconsciously. She’s got a lot of stuff on her plate so she has been present but not nearly enough from what I need her for. Spoke with her today and realized that there’s a lot of shit that she’s upset about and I feel so guilty. Part of me wants to end this friendship to also prevent my hurt from hurting others. Part of me wants to work things out. Part of me is so burnt out that I have this to deal with on top of the break up. I feel like I’ve become a really mean person and it sucks.