Friends think he is too old for me

My best friend thinks a guy I am dating is too old for me. There is a gap of eight years between us, but I have never been more comfortable with anyone. He and I can chat about anything and everything, and there is a maturity in this relationship that I have not experienced before. My friend is not being supportive and avoids meeting me if he is with me. It has created an unnecessary rift between us, and I don’t know how to get her to see things from my perspective. I want this relationship to work, but I can’t lose my best friend in the bargain. How do I fix this?
Your friend is entitled to an opinion and may have your best interests at heart but, as two consenting adults, you and your boyfriend can make any decision that you believe works for you. If there is a rift, it isn’t because of your decision as much as it is about your friend refusing to empathise. Give her time, meet them separately for a while, and allow her to see the impact of this relationship on you. Maybe she just needs to see that you are okay, and that your boyfriend’s presence in your life is positive and not cause for concern. Sometimes, stepping away from a situation allows for a certain objectivity to creep in, and this may happen with your friend too. After all, she presumably doesn’t want to lose her best friend either.

Is it normal for my girlfriend to give her phone number out to other guys and then text them?
Have you talked about it? If they are friends, there’s nothing wrong with this but, if you are concerned about why she is doing this and it upsets you, ask for an explanation. Your girlfriend is entitled to drawing her own personal boundaries and control her private life. As long as this doesn’t affect your relationship in any way, what she does with her number is still her own business.