I agree with all the above comments. Long term (life long?) therapy is not about dealing with just one issue. If you want and need support with different aspects of life when they happen so that you aim to get the most out of life then why not.

There is another point too. Some people have very diffiucult lives. My sister has a learning disability aswell as mental health problems - she needs ongoing support and that comes best from her therapist who knows her very well. I know that for a lot of people therapy is about learning coping strategies and gaining enough insight into yourself so that you can then use those strategies without therapy ie be your own therapist. For many that does work, but others may benefit most from ongoing support and I think are entitled to have it without being made to feel they shouldn't.