This isn’t where you are making assumptions. This is about paying attention and trying to head off problems before they escalate. It is like a fire. If you think it is possible that it will get out of control, get ahead of the problem. If you notice that things are tense or something is off, there is a good chance you are not too far from the truth. Trust your instincts, but handle the matter delicately.
It is better to be proactive than reactive. It is not always easy, if ever, to be able to predict when things are potentially going to derail. If you could really read minds, you would never have any problems or issues navigating life. Heck, you could turn it into a career and then you would neutralize the number one cause of most arguments. Finances. As soon as you notice something is different or things are not quite the way they usually are, get started on identifying the issue and plan how you are going to address it.
Things left unsaid and problems left unsolved have a tendency to build up into a bigger issue down the road. The longer these situations go unaddressed, the more likely it is that things will end up getting worse. You can’t hide from your problems and you can’t pretend that they don’t exist. As soon as you start to see or believe there is an issue, confront it with your significant other immediately. The sooner you take the initiative and address the issue, the easier it will be to resolve.