nursing strike

Brittany
Hey mamas! 
So my little boy (16 weeks)  was nursing great until I went back to work 5-6 weeks ago. Since I've gone back he refuses the breast. I think it's since he's gotten bottles and that's so much easier now that's all he wants. And his pacifier. He's obsessed with his paci. 
I feel like I have tried everything to get him back on the breast. More skin to skin, feeding him with medicine dropper next to breast, tricking him with bottle or pacifier first. He just cries and cries. The only time I can get him to nurse (and this is only half the time) is if he falls asleep wth paci and then I put breast in. 
I've also just started trying new nipples like medela calma and nuk simply natural. 
Has anyone dealt with this issue, and if you have, did your little on get back on the breast? And what tricks did you try that were successful?
I'm ready to throw in the towel I'm so frustrated. 
Thank you!