My question involves real estate located in the State of: VA

Deeded easement for a driveway 15 feet wide each property has 7.5 feet. Neighbor continuously parks on their side of the easement. Blocking our full use of the driveway. Sometimes we have to drive on our land not part of the easement to get around. Had land surveyed and found out that they are not providing their 7.5 feet of the easement more like four feet. The easement says "driveway". Since we do not need their part of the 7.5 to access our property, do we have grounds for termination, since they are obstructing the easement and won't let us use their part. If there is a car parked on their part, they will drive around on our part to get by, they will even drive on our property and have their friends park on our property which is not even the easement. Then ask us why we can't go around. We have a circular drive that we share the other part with two other families which we don't have a problem with and if they need to be in the driveway they tell us. It's just the people on the other side, who think that they have a right to park and leave their cars in the driveway.
We really don't want to spend our money for their inconsideration, but when we sell the house this could be an issue. We would like resolved before we put it on the market. We also sent them a certified letter which they refused. Some of their friends park where they can't be seen around the corner, it is a blind curve and you almost hit someone.