23 year old ready to take control and lose weight!

Hey everyone! I'm new to the forums here, but I've lurked MFP several times before for weight-loss/diet/exercise tips before, so I thought I'd finally join! Here's my introduction (also on my profile page)

This is the first time I've actually attempted to lose weight before. I've never been overweight as a kid or teenager, but I've always been about 5-15 higher than my ideal weight (which is 131 lbs.)

Although there was actually one point in my life when I was down to 127 lbs, but it wasn't on purpose. Any weight I've ever lost before was really just a plain accident.

Then, college happened. I started getting lazy about my eating habits. I didn't have my mom around to make me nutritious dinners, so I turned to fast food. I also got into the bad habit of drinking energy drinks, frappucinos, and other caffeinated sodas in order to (supposedly) study better. I also drank 3 or more alcoholic drinks at parties every couple of weekends.

I've had some success. A year ago, I've cut out all energy drinks. A couple of months ago, I've stopped drinking calorie-bomb coffee drinks (now I only drink black coffee) and soda, for the most part (I only drink it on special occasions, a couple of times a month.) Also, several months ago, I decided I would only have two alcoholic drinks a week (either in the same day or on different days) and absolutely no more than that.

Last year I was at my heaviest (168 lbs) but I decided I would start making a change in early June of 2013. I lost 12 lbs in about 2 months, but then I went on vacation in early August, and my weight went back up to 160. School also started right after then, so I kind of gave up on trying to lose anymore weight. Then, in October, I decided to get back into losing weight again, and I dropped 7 lbs. But then I gained 3 lbs back during the Thanksgiving and Christmas holidays, so I was back up to 156 lbs, where I was in early August before my vacation.

Recently (as of February 2014) I've tried again, with a different primary goal: I want to lose weight so I will be healthier. My main focus now is health, which means that I will need to cut calories, but also make sure these calories are coming from nutritious sources. I also need regular exercise to maintain my health. My other goals are looking good and fitting into old jeans, but health is my most important goal, which comes before everything else.

I've lost about 5 lbs in the last two weeks, so I'm at 151 lbs right now, and I have 20 more lbs to go! Wish me luck!