I remember when I was a 15 year old boy, and yes I will use the word boy even though I supposedly turned into a man at age 13 (Bar Mitzvah) I got my dating advice from my close friends. My closest friend, Joe, would always tell me that you can't be nice to women. You need to command them, put them down, and show your raw dominance over them. At the time I had to think his words had merit because he always seemed to do very well with women. (Obviously, later in life I learned he was full of shit) Anyway, him and I would partner up and head to the mall to hit on women.
One of us would approach, typically taking turns to initiate conversation. Once we thought the women were receptive to having a conversation, we would both talk to them. Joe would dominate conversation and would make fun of me. I would pretend to be sad, one woman would comfort me while the other woman would laugh. The girl that would laugh would be Joe's, while the woman that was sympathetic would be mine. This strategy worked quite well and suited our personalities.
However, obviously this "routine" was not entirely genuine and of course did little in terms of building a true connection and facilitating actually getting to know each other. Thus, this strategy would need to evolve.
Anyway, I probably told this story because it made me feel nostalgic of the fun of hitting on strangers at a mall. But, why is this story valuable for you? It shows that advice from friends can be good and/or bad. In this case, my friend's advice, in the short term of picking up women was probably half decent. But, in the long term, including karma, and building true intimacy, it was disingenuous and not helpful for me or the women I courted.
So, in order to help you decide if your friend's dating advice is any good, I have decided to over generalize but put your friends into two buckets: "Yes" Friends and "Guardian" Friends:
1. The "Yes" Friend - The yes friend simply tells you whatever you want to hear. You get a bad haircut, she tells you, "Wow, I love your haircut. You look amazing!" You have a boyfriend or potential boyfriend that you like and clearly doesn't treat you how to deserve to be treated the yes friend says, "Yea, you are right, give him a second chance." The yes friend is a valuable friend for boosting your ego and having less stressful conversations but she is not a person to get advice from. (At least if you are looking for a honest opinion)
2. The "Guardian" Friend - The guardian friend is 1. your protector and 2. holds you accountable when you do something wrong. This friend has probably known you for a long time and when she sees a current/potential boyfriend not treating you well, you better believe she is going to tell you about it. When the guardian speaks, you better at least listen because she truly has your best interests at heart.
However, in regards to YOUR relationship. It is your decision. My advice is don't rate the quality of the guy, rate the quality of the relationship. If he treats you well, move forward, if he doesn't treat you well, demand better and if he gives you better, awesome! If he doesn't, maybe it is time to move on.
Bottom line, it is okay to listen to all you friends and even listen to the words you find on the internet. But, at the end of the day, you decide what advice is right for you. Some advice will be applicable and helpful, while other advice will not be helpful. Either way, trust yourself and do the best you can. If things with a current boyfriend are meant to be, they will be. If they are not meant to be, that is fine too.