The Unexpected Rebound with My Ex's Friend

I never thought I'd be here. It started when my divorce papers were finally signed after months of legal bullshit and emotional turmoil. I was feeling lost, vulnerable, and aching for something, anything to fill the void left by my ex-wife's departure from our lives. Enter Alex, an old friend who knew both me and my ex-wifey well. We'd kept in touch through the breakup, but never more than friendly texts or calls that were all about being there for each other emotionally. But as I sat at a bar one night after drinking away another day of loneliness, he sidled up to me with this knowing look on his face. It's not like we had any romantic history together or anything; it was just this magnetic connection between us that formed over the years through our shared history and empathy for each other. We both knew there were feelings there but kept them buried because it would have been so, so wrong. Then one night at a party, after too much wine and dancing to upbeat music until we were sweaty and breathless, we ended up alone in his bedroom. It was raw, intense, both of us shedding layers that had been building up for years but never truly acted upon. There was no sweet talk or romantic buildup; it was urgent and needed. I'll spare you the gory details but let's just say there were plenty of explicit anatomical references and positions described with visceral detail. The sex felt like a moment where two people who've been on the sidelines for so long stepped into the center, ready to take what they'd been missing out on. There was no hesitation, only pure, unadulterated desire. Afterwards, we both just lay there panting and sweating, trying to process what had just happened. It was exhilarating but also terrifying, knowing how complicated things would be moving forward. So here I am now, still reeling from that moment. Is it okay to feel this way? Am I crossing a line or is this something more legitimate in the wake of divorce?