Try to stay consistent

This may sound dumb, but for me, the biggest factor that helps me stay consistent and follow through with plans is to make plans that are the easiest possible ways to go while reaching whatever my goal(s) happen to be.

I'm not saying everything is super easy every second. Just changing habits at all involves a certain amount of difficulty, because we're stuck in our current rut metaphorically speaking, and it can take some extra energy to cut a new path and stay on it. For sure, though, there are ways to make that new path harder to reach or follow, and other ways that will make it relatively easier.

Here on MFP, it's not unusual to see people who join up and say they are committed to a whole new lifestyle . . . and sometimes that new lifestyle is a "lose weight fast" calorie goal, plus a bunch of restrictive eating rules, maybe with foods they don't much like, totally cutting out many things they actually do like . . . and then they stack some punitively intense daily exercise they hate on top of that.

Usually those extreme plans fall by the wayside kind of quickly, and their advocates disappear from MFP. I'd like to think that they succeeded as fast as they'd hoped, and went on to continuing robust good health long term. The number of "I'm back" posts in Introductions make me skeptical that that's mostly what happens.

The good news is that IME, those extremes aren't essential. There are quite a few people here on MFP who've succeeded at weight loss, stayed at a more reasonable weight long term, gotten fitter, etc. Most of them are . . . kind of boring, honestly. Personally, I've been maintaining a healthy weight for 8+ years now, follow just under a year of loss from class 1 obese to a healthy weight after about 3 previous decades of overweight/obesity. I'm definitely boring in that way.

I decided I wasn't going to do anything to lose weight that I wasn't willing to continue long term to stay at a healthy weight, except for a sensibly moderate calorie deficit until I reached goal weight. I eat foods I enjoy that add up to reasonable calories and good overall nutrition on average, and do exercise that's so fun for me I'd do it even if it weren't good for me (but it is). It took a while to figure out the best plan for me, but that was a high-return investment of my time. Along the way, it felt like a fun, productive science fair experiment for grown-ups, not a forced march through a drama of sin and retribution for being fat in the first place. YMMV, as may others'.

Exactly what to do is going to vary from one person to the next, IMO. Me, I'm a hedonistic aging hippie flake with a severely limited budget of motivation/will power, and an impulsive nature when it comes to what I want to eat. I think if I could find tactics that worked in that scenario, most more-mature serious grown-ups will be able to do it, too.

So, my advice would be to think about your plan, and make it fit you, plus be as easy as you can make it while achieving progress.

Focus on eating that keeps you mostly full and happy, delivers the nutrition to keep your energy up and your body healthy, has a reasonable calorie content, and is practical/affordable. Include a few treats just for joy, anything you're capable of moderating.

On the activity front, think about ways to add more movement to your daily non-exercise life, and work on finding exercise activity that's ideally fun, but that's at least tolerable and practical. The best solution IMO is an exercise routine that fits into your life well while still devoting enough time and energy to family, social life, job, home chores, and anything else important to you. If you like some gym-y thing, great. If you don't, there a huge numbers of non-gym options: Walking in the park, hiking, biking, swimming, dozens of kinds of dancing, canoeing/kayaking/rowing, skating, skiing, games like frisbee or basketball or whatever, active VR or video games, martial arts . . . I could go on and on, but you get the idea.

Don't be afraid of new activities that seem hard at first. Give it a fair try. Everyone was new at it at some time, and they made progress. So can you. Sometimes things that seem easy at first get boring fast. Things that are more difficult or complicated - but still safe - can stay interesting longer. It's also fine to mix things up over time, if you like.

Usually, a manageable challenge is the sweet spot for both weight management and fitness improvement, not some crazy-extreme thing. Any exercise we enjoy (at least tolerate) so do regularly is 100% more beneficial than some theoretically ideal exercise that we procrastinate and skip at the slightest excuse.

OK, I'm rambling again. Definitely a personal fault, so:

TL;DR: Find a personalized approach that's as easy as it can be while still being effective for you, and avoid extremes or misery to the extent possible. It can work.

I'm cheering for you to succeed, because the results are IME more than worth the effort.