Not sure what to do :(

My wife and I have been together for 19 years, but I feel like the spark is disappearing from her side . How do I bring it back?
I'm 39 and my wife is 42. We've been together for 19 years, so basically most of our adult lives.
I'm North African and my wife is Polish , we met when I was young, sexy and attractive. We lived in Poland before my career advanced and got a job in the uk. We live in Manchester since 2015. over the years, my life has become very centred around my wife and our relationship. I don't have a particularly big social circle and I don't have many close friends since I moved to the uk , which I think has started affecting the way I see myself.
The problem I'm struggling with is that I still find my wife attractive. I still have sexual feelings towards her and I still want that chemistry between us. But I increasingly feel like she is losing that sexual attraction towards me.
There isn't necessarily one big thing that has happened. It's more a feeling I've developed over time. I don't feel that same excitement or jealousy from her anymore, and sometimes I wonder whether she sees me as someone she is comfortable with rather than someone she is genuinely attracted to.
The embarrassing part is that I think she can sense my insecurity.
Because I don't have many friends or much of a social life outside the relationship, I sometimes feel like she knows I don't really have other options. And I worry that this affects how she sees me — almost as if she knows I would never go anywhere, so there is no reason for her to worry about losing me.
Apart from my successful career, I’m also a dj and have the opportunity to meet new people. As some of you may know, having a brown skin in the UK, meaning girls Will not even look at you as a man which I think my wife can feel. Unlike Poland , where my wife back in the days could clearly see that some women are super attracted to me.

I'm not saying I want her to be controlling or constantly jealous. That's not what I'm looking for. I think what I actually miss is feeling desired. I want to feel like my wife looks at me and still thinks I'm attractive, rather than just seeing me as her husband of 19 years.

And I realise that some of this is probably coming from my own insecurities. I'm 39 now, I'm not the same person I was when we first got together, and I don't feel particularly attractive to women anymore.
I also don't want to cheat or find someone else just to prove that I can. I love my wife and I'm still attracted to her. I just don't know how to get that sexual spark back.
So I'm wondering what people who have been together for a long time think.
Is this just a normal stage of a long-term relationship? Can sexual attraction actually be reignited after 19 years?
And should I be focusing less on trying to make my wife jealous or prove that other women find me attractive, and instead work on becoming more confident and having my own life outside the marriage?
I'd genuinely appreciate some honest perspectives, especially from people who have been married for 10, 15, 20+ years.