Remembering the first time

The first time I can remember when I had an erection issue was in my mid-twenties. I’ve had a girlfriend for like five years, but at that point our relationship was fragile. She was out of the country and I’ve met someone else and she was flirting with me. After a few days of flirting, we eventually ended up in my room and I couldn’t get it hard. The thing was that I was hard when we were kissing, but as soon as we got naked, my penis went completely soft. This happened on another occasion too. Eventually, the third time, we were kissing, I was hard, and I just pulled her pants and panties down with no foreplay and penetrated her. Once inside, I could keep my erection no problem.