Subs as friends?

Since Ive come here I've made what I thought were some good sub friends. Some still are, some are not. I've found as the friendship grows, the Domme aspect diminishes for me. Not even sure where Im going with this blog, I think Im looking on an open discussion. To Domes: are there subs that you are strictly friends with? I have had 2 what I consider to be friends subs here. Don't get me wrong, I'm friendly with all subs, enjoy chatting, exchanging ideas etc. But since joining Ive had 2 special friends. One remains, and one doesn't.
Both friendships have gone through bumps, that most friendships do. One survived it, one was real, the other was obviously not. The difference is honesty on both on my part, and the part of the sub. I can not pound home enough, how important honesty is to me. The truth hurts, but never as much as a lie. At least to me. Even if the lie is to "protect" me/my feelings. The fact that the Liar didn't trust my friendship enough to be honest is always more hurtful. My friendship is an amazing gift, and is not given lightly.
The friendship that survived, did so for a couple of reasons. I was able to say, yes I was wrong, I am sorry, and I was able to truly forgive the sub once I received a sincere apology. This is how true friendship is built, friendships stock my Karma bank, like money stocks my Bank Account. Its necessary for me. The friendship that did not survive, because my confrontation on the lies, was harsh (not unreasonable) and was met with defensiveness, and catty behavior. (block and move on) it happens, best to you and yours buddy :)
The funny thing is once that happened, things opened up for me, tribs began to flow from other boys and its been amazing. so iit got me to wondering, is it possible to be "just friends" with subs? I believe yes, but it has to be a very good sub, not a fuck boy, we all know the type. (insert eye roll here.) and you as a Domme have to be honest with your time, expectations etc. If you do not, resentment creeps in, and things are destroyed. At least in my experience. Some say if a sub isn't giving, he isn't useful, and therefore wouldn't get the time of day. Totally respect that, just not my aesthetic.
So subs and Domes alike, what say you? What are your opinions/experiences on subs as non-tributing friends?