Sorry for the long read :) It’s a complicated topic, and below is just a taster.
It’s sad to read some of the comments here on feelings about exercise.
You’re not an idiot and have no reason to be disgusted with yourself. And, those that like exercise don’t hold some magic power or are full of grit or whatever else they like to tell themselves or others.
The tips and tricks you’re after have to affect three different areas: (i) what exercise currently means to you (ii) feelings during an activity, and (iii) your recollection of the activity afterwards and likelihood of repeating it.
Tips and tricks
For (i) what exercise currently means to you:
It sounds like you are in a vicious cycle of failure; you can get out of it. If your ‘why’ is any of the following: lose weight, better health, better numbers, lower cholesterol etc etc then they’re the wrong ‘whys’. They’re abstract and clinical and far off into the future. Research shows, in the long term, these ‘why’s’ are associated with doing the least amount of exercise.
Wrong why leads to -> exercise is a chore -> I should do this -> FAIL and then restart. A cycle of failure.
So, the first trick is to understand how you frame exercise and shift from ‘chore’ to ‘gift’ and ’should’ to ‘want’ to do it.
To solve this, you can choose more immediate rewards that you’d like to get from exercise: fun, energy, improved focus, lifted mood, and connection with others.
For (ii) feeling during an activity:
Don’t do things you don’t enjoy; eventually, you’ll stop doing them.
Feelings during an activity are largely dependent on your current fitness level and the intensity of the activity in relation to your fitness level. Building up the volume at lower intensities, brisk walking, easy cycling, hiking etc, tends to be more enjoyable and gets you into a habit of movement. Jumping into higher intensities often makes exercise feel unpleasant and like a chore. No pain, no gain is completely wrong. Elite athletes spend a lot of time doing easy base-building before sharpening with goal-specific intensities.
You can use ‘reward substitution’ as a neat trick to make an activity more enjoyable. You say you have an exercise bike at home. One thing I do when building endurance is use the exercise bike whilst watching a series on TV. This means you get an immediate reward (watching your favourite show) whilst exercising.
At medium intensities, music or podcasts can help make the perception of effort more manageable.
For (iii) recollection of activity:
If doing higher intensities, one neat trick is called the slope of pleasure. We tend to experience an exercise as more enjoyable and remember it as more enjoyable if, during a higher-intensity session, we start off hard and get progressively easier rather than the other way around.
For each of the three sections, there are loads more tips. You'll get a long way just by finding some forms of movement you enjoy doing consistently and where you can increase the volume. If you can get into that routine, you find people get something called self-efficacy transference - they believe they can do certain activities and begin trying new, related activities.