It sounds like you're in a challenging situation, and it's completely understandable that you want to communicate your feelings to your boyfriend in a way that is clear and respectful. Here are some steps you can take to express your thoughts and feelings effectively:

1. Choose the Right Time and Place

Timing and environment play a crucial role in communication. Pick a moment when both of you are calm and free from distractions. A quiet evening at home or a walk in the park could provide a relaxed setting for a meaningful conversation.

2. Use "I" Statements

When discussing sensitive topics, framing your feelings in "I" statements can help prevent your boyfriend from feeling defensive. For example:

• Instead of saying: "You don’t trust me."
• Say: "I feel hurt when it seems like you don’t trust my judgment about my friendships."

3. Reiterate Your Independence

Make it clear that while you value your relationship, you also value your independence and ability to make your own choices. You might say:

"I appreciate your concern for me, but I want you to know that I am capable of making my own decisions. Just because my friend does something doesn’t mean I will follow suit."

4. Acknowledge His Concerns

It’s essential to show that you understand where he’s coming from, even if you don’t agree. You can say:

"I understand that you see my friend as a bad influence, but I want you to know that I have my own views and values that guide my decisions."

5. Set Boundaries for the Conversation

Clarify that you want to have an open dialogue and that you both can express your feelings without resorting to anger or dismissive comments. You might say:

"I want us to be able to talk about this without feeling like we’re attacking each other. Can we agree to listen to each other’s points of view?"

6. Suggest Compromise

While you shouldn’t have to give up your friendships, suggesting a compromise might help ease the situation. For example:

"How about I invite you to join us the next time we go out? This way, you can see for yourself how I interact with her, and we can all have fun together."

7. Reassure Him of Your Commitment

Let him know that your friendship with your best friend doesn’t diminish your commitment to him. You could say:

"Our relationship is very important to me, and I want you to feel secure in that. My friendship with her doesn’t change how I feel about you."

8. Address the Degrading Comment

If you felt uncomfortable with his comment about your outfit, it’s essential to bring that up too. You could say:

"I wanted to mention that when you asked about my outfit, it made me feel a bit uncomfortable. I’d like for us to respect each other’s autonomy, especially when it comes to how we present ourselves."

9. Be Open to His Response

After you’ve expressed your feelings, give him space to respond. Listen actively and try to understand his perspective, even if it’s difficult. This can help foster a more constructive dialogue.

10. Consider Seeking Help

If this issue continues to cause tension, it might be beneficial to seek couples counseling. A neutral third party can help facilitate conversations and provide tools for better communication.

Ultimately, remember that it’s healthy to have friendships outside of your romantic relationship. A strong partnership is built on trust, respect, and open communication. Good luck!