SG I'll agree with TL, while I was trying to make a constructive suggestion to use less sugar, at the same time I was wondering about the Jello. I've never heard of adding Jello but I'm not any expert at making jam.
The kind I've made I call "refrigerator jam" because it's not made under sterile conditions and must be kept under refrigeration. The recipe is simple, you just add a bunch of fruit to a stock pot and simmer it for a few or several hours, adding only a minimal amount of sugar, no other ingredients. My favorite variety was figs (I had a fig tree) and sliced/chopped lemon including the rind, and just enough sugar to make it a little sweet but not heavily sweet like most jams. I like the less sweet results because they taste more of the fruit.
I suggest you find a recipe that is more conventional, one that doesn't use Jello. If you want pectin then use pectin. Maybe the Jello in your recipe is intended to be a source of pectin (probably in fact). So maybe get rid of the Jello, replace it with pectin, and add some real strawberries.