I agree with what COMF said up to a point - a relationship can be a real distraction when you are trying to focus on reaching a goal.
On the other hand, a healthy friendship can also be a motivator whether the nature of the friendship is romantic or not. Ever work out? Do you think it's easier and more enjoyable with a partner? This is partly because you have someone with whom you're sharing a common goal, and you are encouraged by each other's progress and success.
But then again, romantic relationships tend to consume every ounce of your attention in their early stages, regardless of whether you think you will "allow them" to or not, and that could slow you down. While you may be able to avoid that to some degree by finding someone who is working towards a similar life objective, that's not always easy or ideal.
Certainly a lot to think about.
Another factor is priority - to a lot of people relationships are more important than education and the extra prosperity it can bring. There's nothing wrong with that viewpoint either.
Ultimately, you need to figure out what you think will make you happiest. There is no guarantee that finishing school will make your life immediately better - even if your definition of happiness is material wealth. It does, however, increase your odds.