“Why the heck did the OP’s son give a girlfriend a stuffed animal if it was that cherished?”
Lovesick, hormonal teenagers with underdeveloped prefrontal cortexes…no one ever said they are rational. 
^^^well, hopefully a lesson learned.
Perhaps he wanted to give or share something of great value to him as a token of his feelings for her. Kind of like your boyfriend giving you his varsity jacket in high school.
Perhaps something to comfort her in her difficult home situation.
Expecting rational decisions from guys when it comes to women? Guys twice this kids age struggle with that every day.
^ I’m just saying… it’s not just guys that can be irrational. 
“I would get that stuffed animal back no matter what it took”
“Why the heck did the OP’s son give a girlfriend a stuffed animal if it was that cherished?”
It might well be that the stuffed animal has more memories attached to it for mom than for son. My kids have long given up stuffed animals that I can’t bear to get rid of for better or worse.
Went through similar thing with daughter who was a senior at a Boarding HS. Relationship went into and through freshman year of college. BF spentThanksgiving with us (international) but breakup by boy was ugly ending it literally right before Finals, in the spring. Having made it through “Thanksgiving Dump,” we had considered ourselves lucky. But in truth, it had to end sometime. Kids are too young to commit to a forever relationship.
Our approach was to support our student, and not get involved otherwise. Supporting your young adult is the best thing you can do. Listen, let them know you are available to be a sounding board. Support their healthy thinking and acknowledge the deep hurt. Overall, this will help your student make wise choices going forward and empowering them, and helping them through both the hurt and realization that the sun will come up again the next day and life does go on.
A young man gave D2’s his stuff animal when D2 was in 8th grade. I told her to give it back because it was too personal. I didn’t want D2 to be responsible if something should happen to it. BTW - I would have made D2 give it back to him if she would have kept it and if they have stopped being friends. D2 was relieved that I made her give it back (my mom wouldn’t let me keep it).
I have been through many breakups with D2 (can’t afford any more bags for her). She has never gone back to anyone, except for this current BF. I was quite made at the young man, but I didn’t try to stop her from going back to him. The only thing I am doing is not to have him over at our place until I know he is making my baby really happy again.
I can see that. D2’s “blankie” is still in her closet after many other purges. I would be sad to see it go, honestly. But if she gave it away under these circumstances, I would reluctantly let her handle it; if she didn’t want to deal with him, I’d just encourage her to accept the consequences as a learning experience.
On the topic of why give a cherished stuffed animal? I understand. Here’s my rationale:
When I was a young adult and hopelessly in love, young man and me wanted to exchange meaningfully personal things as a show of love and commitment. This is sort of like the equivalent of wedding rings and vows in realtionships where marriage really isn’t realistic. On some level, adolescents realize they can’t support themselves yet, and get married, but the feelings are similar.
Young fellow gave me his “blood wings,” from jump school. These are the wings that are pounded into your chest signaling bravery, machoism and the like. I gave him my birthstone ring that my grandmother had bought for me when I turned 13. At the time we were both just finishing college.
After the breakup that was difficult, I sent him the wings back letting him know I thought he should have them, and I asked for my ring back. He sent it back, but today, I have no idea where that ring is.
The point being, the stuffed animal was a symbol of love, which was dear to him, a part of himself he was giving toher, but the item itself may not have enduring sentiment, and in the end may not be worth fighting for.
Just to add: In the theory of love and object relations, love is given to us to give to one another. She took his love (stuffed animal) and put it in the trash. She is signaling she doesn’t want his love and doesn’t value it. He should take it for that, and remember that, which will help him move on and get over her.
Whether she actually put the gifts in the trash or just told him she was going to as a means of hurting him and causing drama, who knows? I’m guessing the latter.
^^^yeh, I thought of that…It basically is interpreted as the same thing. She’s telling him she doesn’t want or value his love (at least at that moment).
^^^“at least at that moment” being the operative words.
^^^^yes, for sure
I see someone else has suggested a therapist. I think this could be an enormously helpful gift to your dear son. CBT. There will be many things he can discuss with the therapist and hear from the therapist that he cannot discuss or hear from you. A competent therapist can help teach your son coping skills that can last a lifetime.
Good luck! I’m feeling a little Mama Bear myself after reading your OP.
I bought a special book for S2 when he lost his first tooth. He loved that book and he had taken it to the GF’s house. After four years, they broke up. 2.5 years later, after my heart attack, I contacted the GF and told her I’d gotten S that book and it would mean a great deal to me if I could pay for her to mail it back. (She knew about my medical situation through other friends. She and S2 have had no contact in years.) She sent it back, insisted on paying the postage.
I still haven’t told S I retrieved the book. But it’s here for him and that was I wanted to happen.
I am a big sentimental basketcase. Crying just typing this!
ETA: I contacted S2’s GF when things seemed very on the rocks (I didn’t know she had already broken up with him.). She was gracious, but it was over the line on my part. I didn’t make that mistake again.
When S1 and DIL split up, we asked if we could give DIL our love, and they arranged a time for that. Otherwise, we have not been in touch with her. It makes me sad, but it’s not my choice to intrude. I am thankful that they are very cordial and still have a good relationship. I’m FB friends with her mom, but we both adhere to keeping our children out of the conversation.
@CountingDown so glad she still had the book and returned it!
I’m sorry you and your son are going through this. A child’s heartbreak is hard on the whole family. Hugs.