5 years ago I stopped exercising after the boxing gym I went to closed down and I lost motivation. I figured if I ate right I could keep the weight off (pshh...) Then, I was 128lbs.

So, here I am now, trying to lose weight all over again because of stubborness. lol.
However, I've found it to be quite distressing.
I hopped on the scale today after a week of exercising and found myself to weigh 170... so I was upset, didn't exercise today, and ate way more than I should've. LOL.
I did wash car for a few hours if that counts for anything

So here's what I've been doing...
I figured it'd be best to start out slow and gradually build up.
I ride bike 3-6 miles a day and occasionally I'll pick up the jump rope or a 10lb weight for arms.
I did this for about 3 weeks, then I took a two week break, and went back to it again this past week. (LOL, the "break" wasn't planned or intentional... I had 740 math problems -no joke- and two papers to do... excuses!)
I know I've gained muscle back... much more quickly than I expected (it DOES have memory!),
but I still have ALL of , if not MORE, fat. Maybe I haven't given it enough time yet, but today's scale result was a huge disappointment.
And what's even worse, is I have family coming over on Sunday to take me out to eat AT A BUFFET.
It's more of a Salad bar, but hell, I gain 5 lbs for eating three apples! (I hate genetics.)
...man, I miss those boxing days... I'd eat 3 slices of pizza and burned it all off in an hour at the gym... -sigh-
So anyway,
When I took boxing I had to take in a lot of sugar, but I'm not sure WHAT I should be eating now.
I feel like I've lost that portion of brain that knew everything about health, lol.
I tried Weight Watchers, but I kept -looking- for loopholes so that didn't work. (like they basically say popcorn is nothing...so I'd dine on popcorn 24/7...haha).
I've been trying to eat breakfast every morning like I used to, which usually consists of a cornbread muffin or something while I'm running out the door, Lol.
Other than that,
I don't have time for lunch so I usually skip (It's hard to find time + nutrition in college), and I eat a healthy dinner with all those specific serving sizes ( parents are freaks.)
But sometimes boyfriend pulls me out of the house where I eat a SECOND dinner. It's hard to restrain myself, he's 6'5 and so he's pretty much required to eat like 2500 calories, while I only need 1200.... so he eats all the yummy looking junk and AGGHHH
I'm tempted into it.
So does time of day really matter in what I eat? Like basically, parent's healthy dinner could be equal to a 5pm Lunch, and then when I go out to eat with S.O. (~8PM) It's dinner? LOL.
And breakfast, what if I eat it an hour after I wake up?
As for exercise,
bike isn't really racing heart the way I want it to (though it burns the hell out of legs), so what should I do?
I really hate running, it's so uncomfortable, but if you think it would be best, I'll give it a shot.
I tried to do some routine stuff I used to do in boxing, a couple months ago, but ended up rolling on the floor, in tears, and in some horrible lower-back pain, barely able to move, LOL. I think it was diagnosed as Sciatica or something like that.

I will never attempt to box again without a trainer! hahaha
Also,
I was wondering if drinking too much water maybe expands your stomach?
After I exercise I FEEL great, of course. But I'm horrified when I look in the mirror and see a gigantic pillow of a ...
And lastly,
What do I do about this restaurant thing?
I definitely don't want to turn it down, but I gain weight so easily... I saw something about how you can trick yourself by filling up a smaller plate so you think you ate more than you did?
Does that work?
The genetics on moms side are miserable. mom has to run 5 miles a day to MAINTAIN her weight (she's 5'3, 110lbs). She doesn't even eat much. All of her sisters are horribly overweight, despite their dieting. Then again, they don't do much for exercise.
(I have a sister whose 5'1, 89lbs, never exercises, has a blackhole for an appetite.... wish I got Dad's genes.)
Any Advice?