Have you tried to discuss this is a calm way - a non-judgmental way . IMO it's fine to masturbate as long as the other is being satisfied. You could start by saying, you think it's fine to self pleasure but you also want intimacy - then go on from there.

I think sometimes one partner can become lazy - it's easy to just do it and be done lol. Would he be receptive to talking about this Bebop? Sounds like you both need some quality time together - think of what you both did together at the beginning of your relationship. Tell him you miss him and that connection you had before. Maybe you can write him a letter if that would make you more comfortable. If you are going to talk about it - the tone is very important......you don't want to sound accusatory/blaming. Most men are very sensitive about their sexuality. Are you fine with him masturbating as long as he satisfies you?