I’m confused about relationships in Islam-am I misunderstanding everything?

Assalamu alaikum, everyone. I’m a 24-year-old Muslimah living in the West, and honestly, I’m really struggling to understand what’s expected when it comes to relationships in our deen. My parents never really taught me much beyond “no intimacy before marriage,” and I only found out later that there are actually clear guidelines-like no casual dating, no physical contact, and getting to know a potential spouse in a halal way with a wali present. So I’ve been trying my best to stick to that. I’ve never had a boyfriend, I stay away from parties, and I don’t have male friends or chat with guys unnecessarily. But here’s where it gets confusing: my own family doesn’t follow the same rules. My 18-year-old brother has a girlfriend, which didn’t shock me since dating is common in our culture. What did shock me was my mom encouraging him to meet other girls while he’s in a relationship, saying it’s okay as long as his girlfriend doesn’t find out-which is basically cheating. She’s also totally fine with him going on a week-long vacation alone with his girlfriend. When I questioned it, she literally said, “It’s not like they’re going to have sex.” SubhanAllah. I shot back, “Then why can’t he just move in with her tomorrow if rules don’t matter?” We ended up in a huge fight. She also tells me I’ll never find a husband because I’ve never dated, and that no man will want someone like me. Once, she pressured me to talk to a guy, and I kept refusing because I knew things about him and didn’t want to expose his sins. But she kept pushing, so I told her: he’s not religious, he’s had multiple partners, and even his private pictures were leaked. I thought she’d understand, and I explained that I want a practicing husband who fears Allah and hasn’t been in haram relationships. She just laughed and said, “Go to the mosque then. Good luck.” Now I’m doubting myself. Did I get Islam wrong? Are we supposed to date, especially in non-Muslim countries? Everyone I know meets their spouse through partying, apps, or social media, and I’m not comfortable with any of that. My parents have even told me to go to nightclubs, saying, “At least you don’t have to drink.” Like, what? You wouldn’t expect a hijabi in a club full of drunk people and drugs, so how is it any different for those of us who don’t wear hijab? We’re all Muslim. My mom says I shouldn’t think this way because I don’t wear hijab (no one in my family does except one grandma and an aunt who just started) and I don’t pray all five prayers (inshaAllah I’m working on that). But that’s exactly why I feel I should avoid dating and parties and seek a pious husband-I’m already struggling with sins, so why add more? I feel stuck. I want to follow my religion, but everyone around me acts like dating and premarital relationships are totally normal. Almost no one saves themselves for marriage or looks for a religious partner. It honestly scares me. Did I misunderstand everything? Is dating the only way to find a spouse in a non-Muslim country? Will I really never get married, like my mom keeps saying?