Disregard them they're being a faggot. There's a shred of truth to "just b urself lol", but obviously you have to change something. Trying to forcibly change your personality for women is really really stupid though. Women pick up on social shit a hundred times better than men, even the sheltered ones. It's one of the areas they legitimately beat men by nature.
The good news is that women let shit slide all the time for better or worse. If you focus on improving good things about yourself, and minimize rather than eliminate the bad parts, it'll be a lot more effective for not only women but your entire life in general. Accentuate your positive traits and find the silver linings in your negative ones. Basically, work around your personality. Gonna speak in general terms here rather than anyone in particular.
Do you like being nice m'lady tipper? You don't have to completely stop, just develop a better sense of who to be nice to and when. Where most guys would let positive reinforcement go to the wayside, one could use an ordinarily negative trait to their advantage and be romantic and a stress-reliever. Instead of worrying about niceness/dickness, focus on directing those beta orbiter in a constructive manner. Everybody likes an uplifting and inspirational person in their life, just let them know they can't take advantage of it.
Another one, being quick to anger, you can use that to your advantage too. Don't force yourself not to get mad in a situation that calls for it. That shows off strength of character. Rework latent anger into passion, being protective of friends/family, etc. If you do end up lashing out when you really shouldn't have, acknowledging it shows off a ton of positive qualities, as long as you aren't begging to be forgiven like a cuck.
You can apply this to physical traits as well. While it may sound roundabout and stupid for a fatty to not focus on losing weight, learning to be constructive in ways that minimize the effects and possibly even lose fat in a logically roundabout is actually a really good idea. Instead of "trying to lose fat", work on "trying to eat healthy". Losing fat can be a byproduct of it and it's a whole lot better than pulling a Trashman weight loss diet to just "lose fat".
Basically, don't focus so much on changing personality, as much as building on it. Find out how to work around your flaws and aim to do things that either minimize/fix-as-a-result-of negative qualities or boost good ones, and find the good in the bad. It sounds like dumb optimism faggotry I know, but it's good for you.