Can my marriage be saved?

We have been together 20 years and I’ve put on a lot of weight early on and got various reasons it’s taken me forever to get to a point where I can actually commit to loosing it. My husband wants an open marriage because he says he loves me and only wants me as his wife but he needs to sleep with sexy women. I’m open to this coz I feel like I owe him but I guess what I’m asking is if I loose the weight and open our marriage will find the spark again
Can my marriage be saved?
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