Brazilian mom is making me (Canadian woman) uncomfortable with her comments about her son's penis, before our wedding. Advice please!

I am a white Canadian woman who is about to marry my Brazilian man in four days!! We’ve got a great relationship, we have similar values, wants and needs, communicate how we feel easily, and never speak to each other disrespectfully. In the last four years, we’ve worked through any disagreements easily and without fuss. It’s a dream. I feel incredibly lucky. 

But. Then his mom came into the picture. She just arrived to Canada for our wedding. She will be staying with us for the next month, and we have just met in person for the first time in four years. 

My partner has communicated with me many times in the past that his mom is a bit of a hippy and can be “a lot” and has been jealous of his partners giving him attention in the past. He said in Brazilian culture, moms are more affectionate with their sons and it’s different than Canadian culture. 

This I totally understand, and I prefer the warmth of our Brazilian friend group over my Canadian ones! It’s so nice. 

But I find his mom almost treats my partner like a boyfriend in a way, she can be very clingy, and touchy. I don’t mind this part of it, if it wasn’t for what I’m going to say next. My partner’s mom also makes sex jokes about him or around his hard dick and it’s made me really uncomfortable. Her talking about his hard dick in any kind of joking way, or his body, makes me feel gross. Jokes also around how I'm a slut and just fell for his dick?

I didn’t think it was going to bother me as much as it did, but we tried to have sex the next day after these comments, and I couldn’t because I couldn’t stop thinking about his mom - when I seen his dick. Sexually, I feel weird and like his mom is turning me off completely. God help me. 

So my question is this - is this REALLY how Brazilian moms are? Or is she going way too far? I want to be sensitive to culture but I feel is messing up my sex life. My partner is understanding, but I feel like he’s so use to her behaviours that he isn’t understanding how important and weird this is to me. It’s the first time I felt like my partner didn’t have my back. Before I go any further, I wanted some advice from the community.