I'm really sorry you're feeling like this. It sounds like a very tough situation, and it's important to navigate these emotions carefully and thoughtfully. Let's try to break this down step by step.

1. **Communication is Key**: First and foremost, you need to have an open and honest conversation with him. Let him know how his actions are making you feel without accusing him of anything. Use "I" statements like, "I feel hurt and neglected when I see you spending more time with her than with me." This helps in not making him feel defensive right away.

2. **Listen to His Side**: Allow him the space to explain his perspective. Maybe he has reasons for his behavior that you haven't considered. It's important to listen without interrupting so he feels heard too.

3. **Address the Accusations**: If he's calling you toxic for asking about his relationship with this girl, it might be worth discussing why he thinks that. Is it possible that the way you're asking could be coming off as accusatory or controlling? Finding a gentler way to express your concerns can sometimes help.

4. **Rebuild Trust**: If there's any trust issues on either side, they need to be addressed. This might involve setting some boundaries that both of you agree upon. For example, maybe you both agree to limit time spent with friends of the opposite sex, or at least ensure that time is balanced with time spent together.

5. **Reconnect**: If you’ve been on your phone a lot, maybe he's feeling a bit neglected too. Try to consciously put down your phone when you’re together and engage in activities you both enjoy. Rebuilding that connection can make a big difference.

6. **Evaluate the Relationship**: If despite all your efforts, things don’t improve, it might be necessary to take a step back and evaluate if this relationship is healthy for you. Sometimes despite our best efforts, some relationships aren’t meant to be, especially if they cause more pain than joy.

Remember, a healthy relationship should be based on mutual trust, respect, and open communication. It might be helpful for both of you to consider couples counseling, where a neutral third party can help mediate and offer strategies to improve your relationship.

Take care of yourself and prioritize your emotional well-being. You deserve to be in a relationship where you feel valued and respected.