The elusive truth is that there is nothing stress-producing in the physical world. Things simply are. Molecules move. Light and sound appear.
Find the beliefs that are strangling your feelings, challenge them for your sake as well as theirs, and see how it feels to love someone without a thought about the future, simply for who they are today.
Stress is the negative whirlwind of emotions that gets imposed on top of our stimulation and engagement.
We need to distinguish between stress and stimulation. Having deadlines, setting goals, and pushing yourself to perform at capacity are stimulating. Stress is when you're anxious, upset, or frustrated, which dramatically reduce your ability to perform.
Worrisome thoughts and their resulting feelings are a form of self strangulation. They not only strangle your emotions. They affect your physical life as well, and your ability to focus and get things done.
People often say that stress is a motivator. What we're referring to when we say this is really better described as stimulation and engagement.