Is it cheating if I accepted another man's (he's disabled) proposal out of compassion?

My boyfriend (30 M) and I (28 F) have been together for 6 years. I want to keep my relationship but at the same time help out my disabled, childhood friend out (28 M) of compassion. He had an accident several years ago and is paraplegic as a result. He is bound to a wheelchair. He knows I don't love him but has proposed last month. The thing is I have accepted it out compassion. We have agreed everything (even the ceremony) will just be by name. He hasn't had any luck in relationships ever since his accident and wants to appear like a normal son to his parents and others. He said I can still keep my relationship.

We haven't done anything romantic nor physical so no cheating. I'm not going to live with him. I'll just help him with some of his medical needs sometimes when I visit him. My boyfriend already knows about all this and feels as if he got cheated on or something. He wants me to cancel the deal already. Well to be honest, I liked the ring and I've accepted it so I'm thinking for moving forward with the deal.

Is accepting my disabled friend's proposal out of compassion cheating? Like mentioned, there is nothing going on between us (nothing physical nor romantic) and this is just a bargain.

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3 d
My friend always had feeling for me but it's ok with treating this as a bargain and doesn't mind that I don't love him. At the same time, I have to admit I'm trying to get a reaction from my boyfriend too.
Is it cheating if I accepted another man's (he's disabled) proposal out of compassion?
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