Accountability is a huge aspect of changing your lifestyle. You should definitely reach out to your family, friends and people around you so that your goals can possibly become their goals. You never know if you trying to do better will inspire them to be better. People need a support system and who better else then a work out buddy.
A work out buddy has many benefits. A work out buddy can keep you motivated, hold you accountable when you want to eat poorly and two people looking up/researching is better than one. A workout buddy can also drive competition, if your friend lose a pound it might motivate you to want to lose a pound. Also it is good to have somebody to share your struggle with and it is harder to flake on a scheduled work out when some one is expecting you. Also if you talk while running you burn more calories.
A negative aspect of working out with someone is that you have to work around some one else schedule. If you are easily distracted a work out buddy is really a bad idea. I personally do not like workout buddies because they are such a distraction.
So it is a more of a personal choice but has pros and cons.