Is it possible for two gays to have unhealthy sexual relationship?

Any "forcing" of sex is, by definition, unhealthy. If someone feels compelled to do things they aren't comfortable with, which may happen for the sake of maintaining a relationship that is otherwise compatible, I would still say that this is unhealthy, insofar as this would be a symptom of a lack of honesty and compromise in the relationship.

What I find interesting is just how rigidly some people adhere to the "top" and "bottom" roles. This causes problems when both partners are in the same category. Even then, if only one partner is willing to try the other position, it won't work either, for obvious reasons...It is obviously better if both partners were, at least a little bit, versatile, or, failing that, some explorations should be made into the vast realm of non-penetrative gay sex...

 

This rarely happens. If it does ever happen, then its incredibly unhealthy and toxic situation for all involved.

For the most part, couples who are both tops or bottoms will usually 1) learn to have great sex without involving anal 2) incorporate toys into their play 3) open their relationship to find a third person they can "share"

What does happen more often than not is that most people have a preference and usually one person will care less about the position than the other.

 

I second everything greatwhale said, especially the suggestion of exploring all of the enjoyable sexual things you can do together that don't require penile penetration; and be open to trying out the less passive role in anal sex as I'm sure the anatomy will be "up for the task" when the spirit is playful and loving and there is a lot of hot foreplay.