Husband had a “friend with benefits” before we were together- is it pathetic to be hurt?

My (29F) husband (31M) and I have been together 8 years. We were strangers in a recreational soccer league, and after a few months of getting to know each other, we started dating. We have been inseparable since. We had a fairytale romance, proposal, and were married a year and a half ago. I was sure he was “The One” after just a few months dating. After a year, I knew I wanted to spend my life with him. We have been able to talk through any difficult issues we have, and have had a smooth ride until the last few weeks. <br><br>We met up with an old soccer teammate of his after a game that had been cancelled, and I never realized he had a friendship with this person (25M). Whoops, my bad. It was nice to see him and have a drink together. Later that week he said something about “happy birthday bro!” to this person, and I asked if he was the guy we met up with. He said yes. I asked when their birthdays are, and if we could get them a cake to celebrate. He said the guy’s birthday is in December and his is in October, and they don’t care about birthdays so it’s fine. I was a bit confused by the timeline, but didn’t think much of it. <br><br>This weekend, I was cleaning out his old golf bag and found a card. As I was reading it, I remembered it was his birthday card from the guy we met up with- Happy 30th birthday! I had totally forgotten his birthday last year, and I felt like an idiot. I said to him, “Oh man I’m such an idiot. I totally forgot your birthday last year. I’m sorry!” He just said “no worries, we didn’t do anything” and I dropped it. <br><br>Tonight I was looking at the necklace he gave me for our anniversary last year. I opened it, and saw that there was an extra card in it from the same guy. It said “Happy anniversary, you guys are meant to be, and [my name] is as beautiful as you described her“ with his initials. I was absolutely floored and felt like I had been punched in the gut. I confronted my husband, but he had already anticipated that I would see the card at some point. He said the guy was someone he had been seeing casually from 2016-2018. He said the guy had a huge crush on him and followed him around, even moving to his city for him. He said they were never official, and that the guy just liked to do favors for him and make him gifts. He never intended for me to see the card, just didn’t want to throw it away. <br><br>I am hurt by this, and it makes me feel sick to my stomach. Is this pathetic? I feel like I’m overreacting by a long shot. <br><br>TLDR: my husband’s ex side piece is still in his life. Am I justified in feeling hurt by this, or am I overreacting?