Hi Toadneedshelp,
The article Haylen posted is excellent and worth reading. I suggest that you set your goals as realistically as possible. It's not so much how much you do, but that you do something. The hardest part is often getting started when you're not feeling like it. Set your goals at the beginning of each week, and re-evaluate at the end of the week. If there are problems, like you always say you'll do it after work, but you're too tired, then set the goals for other times.
Another problem is all-or-nothing thinking which almost always ends in burnout. All-or-nothing people will plan on doing, or actually do, 7 days in a row, and then if they miss a day all is lost because they failed, even if they did 7 days in a row! They also "have to" do long workouts. But even if you do just 20 minutes of hard cardio, or 15 minutes of resistance exercise, just a few exercises, it's good enough to get your fix.
As for what you report, you might want to change your workout at 3 months since that's when you know you burnout. It's good news if you can get in 3 months. Just know you're going to fatigue after that time, and plan ahead for it. Maybe hire a personal trainer once every 3 months for a tuneup or new workout. Maybe have some objective measures of your progress. Have your body fat measured, or circumferences, or a submaximal bicycle test to test your endurance. All these things can be done at the gym The standard circumference measurements are arms (flexed and relaxed), chest (after a normal exhale), shoulders (the widest part), waist (the narrowest part below the ribs and above the belly button), abdomen (across the belly button), buttocks (at the maximum extension of the buttocks), gluteal/thigh (high on the thigh at the groove where the buttocks end), mid-thigh (halfway between the crease in the groin and the top of the knee cap), and calf (at the maximum circumference, either with leg hanging freely off a table or with legs 8 inches apart and weight distributed evenly). Keep the tape horizontal during measurements and pull the tape lightly so it indents the skin only slightly.
Finally, it may not be realistic to expect to love exercise all the time, or even at all. It's nice if you do (like if you dance, or play a sport for your workout, but it may not be realistic. Sometimes it's just hard to do it, like you just don't want to. You're not alone. Even the most seasoned exercisers don't always feel like it. But you put one foot in front of the other and make it happen. You know you'll keep going once you get started, and you know you'll feel better after.
You could post here every day if you like. If you want,post your workout, and then when I answer questions, I'll give you some feedback. And you may get some help and support form others too. Why don't you give that a shot for now and see how it goes.
Take care,
Rich