How can I end things with a guy in his 30s who doesn't treat me seriously?

I would appreciate your understanding as I share some context: I (a woman in my 30s) reconnected with my boyfriend (a man in his 30s) after knowing him since high school. Back then, he was much younger than me, and I didn’t give him much thought—just the typical "cute kid syndrome." A decade later, following my divorce, he reached out, and we quickly hit it off. While my divorce wasn’t particularly messy, the relationship with my ex-husband was complicated. When my boyfriend and I got together, I was dealing with PTSD, depression, and undiagnosed anxiety. It was a difficult time, but my boyfriend has been a steadfast support, always lifting me up and reminding me of my worth. Now, to the challenges we’re facing: my boyfriend moved in with me and my kids during the pandemic, agreeing to find a job since I couldn't support both him and my children. Unfortunately, years have passed, and he has yet to secure a stable job. He occasionally earns some income through side projects, but it’s barely enough. When he does manage to make money, he tends to splurge on gifts for others while I’m left worrying about bills and household expenses. Whenever I try to discuss these issues, he responds by saying that if the roles were reversed, supporting me and my kids wouldn’t be a problem for him. However, that’s not the case—I have been financially supporting him for the past five years. Additionally, he often dismisses my concerns about our relationship. Having experienced childhood abuse and a toxic marriage, I sometimes struggle to express my emotions healthily. I tend to bottle up my feelings until they reach a breaking point, leading to stressful situations. Recently, I’ve been feeling overwhelmed more frequently, and any added stress pushes me closer to losing control. My inner voice that questions whether this relationship is working is growing louder with each argument or moment of high stress. During fights, I’ve found myself expressing doubts about our relationship, but he counters with remarks like, “You can’t break up with me every time we argue.” I can understand why he feels that way, given that I’m good at hiding my emotions until I can’t anymore. I’ve told him that he doesn’t truly hear me until I mention our relationship’s viability, yet he responds by saying it’s hard to take me seriously because I seem “cute.” For the record, being called “cute” when I’m frustrated is not helpful. In fact, during one recent disagreement, he likened me to an angry Chihuahua barking at a giant. I’ve attempted to calmly express my feelings and discuss a breakup, only for him to assure me that we can work through things and that I’m right about my concerns. He professes his love for me and my kids, which only adds to my guilt for letting the situation deteriorate when I should have set firmer boundaries long ago. I’m at a loss about how to end this relationship when he doesn’t take me seriously and uses my guilt against me. I could really use some advice on how to navigate this situation. Thank you.