My(26F) husband(27M) passed up a promotion and a bonus at his work because he refused to get recognition for his work

My(26F) husband(27M) hates getting attention from anyone for anything he did not matter how hard he worked for it. He didn't walk at our HS graduation, graduated marine basic alone, didn't walk for college graduation, and he was painfully uncomfortable at our wedding. About a month ago his work asked him to design something (he didn't tell me) but he did it in 2 weeks. But he credited his co-worker with his design (he's an aerospace engineer) and the co-worker got promoted and got a hefty bonus. He told me about it yesterday a week or so after the co-worker got a party and took all the credit for something my husband did. This isn't the first time and I'm tired of my husband letting other people take credit for things he works very hard for. How can I maybe get him to stick up for himself next time he is assigned a similar task.
PS. If it sounds like I'm mad at him about the bonus because we are barely paying bills its not. He spends our money on necessities and then treats me to what I want but never anything for him.
TLDR: My husband is a very shy man and hates attention which led to him crediting a co-worker for his design and that co-worker got a promotion and a bonus. I want him to stick up for himself but I don't know how to approach it.


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