Do two "half" boyfriends make a whole?

I was just looking back at some old posts and theres one from January about having two men in my life and neither one giving me everything I need but somehow the combo of the two making me fufilled in a warped way. And now, ironically enuf, I find myself months later in the same situation just with two different men. And maybe this is the main reason I am juggling them both- because neither one of them wants to step and make me their own- and I need that fufillment- I have them both to fill different needs. I need to have all of these things in one man but unfortunately right now I dont have that. So Steven gives me what Ryan cant right now. But is having Steven in the here-and-now going to affect the down-the-line with Ryan? Or am I still holding out false hope that Ryan and I will be together some day? Altho the feeling when I am with him is so right, and I know that slowly building our friendship is the best foundation for a real, lasting relationship, part of me is scared to stay in this place too long for fear of going to that friends place and never coming back from it. Maybe thats why I am still occasionally sleeping with him despite knowing that would kill Steven...cuz I want to keep the fires burning. But you know, I think its mostly just me giving into my desire and trying to find excuses to justify it. Ryan knows Im hot for him and maybe if we dont do it for a while, it will leave him wanting even more and itching that much harder to make me his own. I cant stop hanging out with him tho! I want him in my life. I need him in my life. I cant imagine him not being in my life. He fufills that emotional need for me. I feel like I can tell him anything and everything. I feel like he will always listen to my point of view. I feel like he truly cares about me as a person. So maybe I let him...and I let Steven fufill the physical need...and see how much longer I can go on having two half boyfriends!