Well- I'm glad you are here. You will be able to gets lots of support here. I understand about the "I'll deal with it when it's an issue" mindset. So- now it is an issue and you are dealing with it by reaching out to others that understand!
The fact that this is your first relationship is probably going to make it more emotional for you.
When relationships end, we have to go through a grieving process which is natural. The average time required for grieving is 25% of the time of the actual relationship. For example- the average grieving period for a 20 year relationship is 5 years. It could actually range from something like 2 years to 8 years for example.
So- for a 20 month relationship- the actual grieving process would take about 5 months.
The reason I mention this is because it is so easy to fall prey to the ideas about relationships by listening to songs on the radio. The ideas of "I can't live without you" and "You are my everything" etc.
When a person is remaining aware of the fact that relationships end .....and mine might end and if it does I will go through a normal grieving process and then move on with my life.
It helps minimize the desperate energy that goes along with the idea that I can't survive a break up....which CAN definitely make the partner feel trapped and stifled.
The key to life is in being fully engaged and peacefully detached simultaneously and authentically in each moment.